"I don't know if I have a choice anymore." [Edward's] voice was almost a whisper. "I was wrong–you're much more observant than I give you credit for." (8.203)
For Edward, being with Bella is a compulsion, rather than a choice. He initially tried "do the right thing" and stay away, but his attraction to her (and her blood?) is just too strong.
"Do you want to ride with me today?" [Edward] asked, amused by my expression as he caught me by surprise yet again. He was really giving me a choice – I was free to refuse, and part of him hoped for that. It was a vain hope. (10.6)
Edward is giving Bella the choice of whether to be with him or not, but is it really a choice? Bella seems to think she is absolutely incapable of resisting his "offer."
My decision was made, made before I'd ever consciously chosen, and I was committed to seeing it through. Because there was nothing more terrifying to me, more excruciating, than the thought of turning away from him. It was an impossibility. (12.148)
Bella speaks of her decision to spend the day with Edward on Saturday. She makes it sound like she has no conscious control over choosing to be with him – if he's available, she's in.
"It took everything I had not to jump up in the middle of that class full of children and–" [Edward] stopped abruptly, looking away. "When you walked past me, I could have ruined everything Carlisle has built for us, right then and there. If I hadn't been denying my thirst for the last, well, too many years, I wouldn't have been able to stop myself." (13.100)
Edward, like the other Cullens, has made a conscious choice not to prey on humans. It took every bit of willpower Edward had not to suck Bella's blood upon first meeting her. For him, it's a battle between his monstrous instincts and his more human conscience and intellect.
[Edward to Bella:] "But I resisted. I don't know how. I forced myself not to wait for you, not to follow you from the school. It was easier outside, when I couldn't smell you anymore, to think clearly, to make the right decision. I left the others near home – I was too ashamed to tell them how weak I was, they only knew something was very wrong – and then I went straight to Carlisle, at the hospital, to tell him I was leaving." (13.109)
Edward originally sees leaving the area as his only option if he's going to maintain his "vegetarian" diet. His longing for Bella's blood is overpowering, and after how hard he and the Cullens have worked to maintain their diet and blend into the human world, he doesn't want to destroy the life they've built.
"No, that's just Carlisle. He would never do that to someone who had another choice." The respect in [Edward's] voice was profound when he spoke of his father figure. "It is easier he says, though," he continued, "if the blood is weak." (14.22)
Unless a person is dying, Carlisle would never transform them into a vampire. He sees it as a last resort. Later, when Edward refuses to turn Bella into a vampire, we learn that he shares Carlisle's view on the matter.
I pushed the terror back as well as I could. My decision was made. It did no good to waste time agonizing over the outcome. I had to think clearly, because Alice and Jasper were waiting for me, and evading them was absolutely essential, and absolutely impossible. (21.76)
Bella sees no range of possibilities. Either she attempts to save her family, or she runs away and risks them getting hurt. Because she values her family so highly, she chooses to sacrifice herself.
[Carlisle to Edward:] "It's your decision, Edward, either way. I can't help you. I have to get this bleeding stopped here if you're going to be taking blood from her hand." (23.47)
Edward has a difficult decision to make: he can either let Bella transform into a vampire (which will naturally happen, since she's been bitten by James), or attempt to suck the venom out of her blood and save her human life. We know that Edward is determined for Bella to remain human, but we also know that he's terrified of coming near her blood, for fear of loosing control and killing her.
"Edward!" I screamed. I realized my eyes were closed again. I opened them, desperate to find his face. And I found him. Finally, I could see his perfect face, staring at me, twisted into a mask of indecision and pain. (23.49)
Edward's position is a tough one, and Bella sees that.
[Bella to Edward:] "Renée has always made choices that work for her – she'd want me to do the same. And Charlie's resilient, he's used to being on his own. I can't take care of them forever. I have my own life to live." (24.216)
Bella tries to convince Edward to turn her into a vampire. She explains that her parents have never considered her when making their life choices, and they'd want her to pursue what would make her happy. Do you buy this argument? Imagine Bella as a young vampire – would it be safe for her to be near her parents? Would she even remember her human past? Has she truly thought through the implications of her decision?
"You can't really believe that I would give in so easily," [Edward] said with a sour edge to his mocking tone.
[Bella:] "A girl can dream."
His eyebrows rose. "Is that what you dream about? Being a monster?"
"Not exactly," I said, frowning at the word choice. Monster, indeed. "Mostly I dream about being with you forever." (Epilogue.199-202)
Bella has decided that she wants to be with Edward forever, and the only way to do that is by becoming a vampire. Edward, however, has had decades to think about human life and vampirism, and he is absolutely against Bella becoming a "monster."
"Did you ever think that maybe my number was up the first time, with the van, and that you've been interfering with fate?" I speculated, distracting myself. [...]
"That wasn't the first time," [Edward] said, and his voice was hard to hear. I stared at him in amazement, but he was looking down. "Your number was up the first time I met you." (8.213, 214)
Bella seems to think that her life isn't only influenced by choices, but also by fate. Here she implies that she might have been "destined" to be killed by Tyler's van, and every minute she continues to live is just bonus time. Edward, however, worries that his choice to remain in her life will eventually mean her death. At the end of the novel, Edward contemplates leaving Bella because that might be "what's best" (24.273) for her.
[Edward to Bella:] "You were right – I'm definitely fighting fate trying to keep you alive." (9.177)
Is Edward is fighting fate? Does Bella simply have a propensity for trouble, or do the choices she and Edward make put her in danger? If she does have a natural propensity for trouble, is Edward's falling in love with her another example of trouble, similar to Tyler's van skidding toward her?
[Edward to Bella :] "That's a good question, and you are not the first one to ask it. The others – the majority of our kind who are quite content with our lot – they, too, wonder at how we live. But you see, just because we've been…dealt a certain hand…it doesn't mean that we can't choose to rise above – to conquer the boundaries of a destiny that none of us wanted. To try to retain whatever essential humanity we can." (14.231)
Most vampires do not fight fate. They follow their natural instincts and feed on humans. The Cullens, however, make the conscious choice not to harm humans. It's hard, but in return for their sacrifices, they have clear consciences.
[Edward to Bella:] "I know that at some point, something I tell you or something you see is going to be too much. And then you'll run away from me, screaming as you go." [Edward] smiled half a smile, but his eyes were serious. "I won't stop you. I want this to happen, because I want you to be safe. And yet, I want to be with you. The two desires are impossible to reconcile…" He trailed off, staring at my face. Waiting. (16.52)
Edward feels fate has dealt him a bad hand – a total catch-22. Edward decides the best compromise is to let himself be near Bella, and try his hardest not to think of her as a "piece of meat." However, since he seems to be unable to leave her, he hopes that she will make the decision herself.
[Edward to Bella:] "They're still there." He shrugged. "As they have been for who knows how many millennia. Carlisle stayed with them only for a short time, just a few decades. He greatly admired their civility, their refinement, but they persisted in trying to cure his aversion to his 'natural food source,' as they called it. They tried to persuade him, and he tried to persuade them, to no avail. At that point, Carlisle decided to try the New World. He dreamed of finding others like himself. He was very lonely, you see." (16.62.1-9)
Carlisle is defined by his choice to maintain his human-free diet. Most vampires, as Edward tells Bella, have a completely different philosophy from Carlisle's. Though Carlisle's decision has led to isolation, he has stuck to what he believes is right.
Slowly, slowly, my thoughts started to break past that brick wall of pain. To plan. For I had not choices now but one: to go to the mirrored room to die. I had no guarantees, nothing to give to keep my mom alive. I could only hope that James would be satisfied with winning the game, that beating Edward would be enough. Despair gripped me; there was no way to bargain, nothing I could offer or withhold that could influence him. But I still had no choice. I had to try. (21.75)
Bella knows her life is over. She hopes that James will be happy enough with her that he won't kill her mother. On a separate note, Bella frequently claims that she has "no choice." Do you agree? Does she truly have no other options?
I was determined not to lose myself at this point, now that my plan was successfully completed. There was no point in indulging in more terror, more anxiety. My path was set. I had just to follow it now. (22.60)
Bella is following what she believes to be her destiny to James and death. Now, it's all about tactics.
"Edward, you have to do it." It was Alice's voice, close by my head. Cool fingers brushed at the wetness in my eyes.
"No!" [Edward] bellowed. (23.38-39)
What's going on here? Is Alice is trying to convince Edward to let Bella become a vampire? He seems mighty upset by the idea. All the same, Edward has a decision to make: he can either let Bella become a vampire, or try to save her by sucking out her venom-infected blood.
[Edward] heard the change in my tone. His eyes tightened. "I don't seem to be strong enough to stay away from you, so I suppose that you'll get your way…whether it kills you or not," he added roughly. (24.188)
Edward feels that he has a choice to make. He believes that it would be best for Bella if he left her, but he's unable to make himself walk away from her. Does this make him weak?
[Edward to Bella:] "I brought you to the prom," he said slowly, finally answering my question, "because I don't want you to miss anything. I don't want my presence to take anything away from you, if I can help it. I want you to be human. I want your life to continue as it would have if I'd died in nineteen-eighteen like I should have." (Epilogue.156)
Edward has a different life philosophy than Bella. He wants her to enjoy her average, human life and not miss anything.