To reach my brother's room, you actually have to leave the house, which is exactly the way he likes it. (1.1.54)
Jesse's a chicken-or-egg situation: Did he isolate himself because his parents left him alone too much, or did they pull away because he isolated himself?
"[My parents] don't really pay attention to me, except when they need my blood or something." (1.2.17)
Dang, some kids' parents don't pay attention to them unless they need the trash taken out or the lawn mowed. This is pretty extreme, and makes Anna feel even more objectified, like a mass of organs instead of a daughter, or even a person.
This is when I realize that Anna has already left the table, and more importantly, that nobody noticed. (1.4.52)
This is from Brian's point of view. At least he noticed, right? Even if he was a little late… that's more than we can say for Sara, who is focused completely on Kate right now.
I look for places like me: big, hollow, forgotten by most everyone. (3.3.17)
Jesse says a lot about himself here. He's the one in the family voted Most Likely to be Forgotten—he's so forgotten, he barely knows himself, and he chooses to fill those empty places with fire.
They called [Julia] Freak, because she wasn't one of us. (3.6.52)
Let's add Julia to the list of people who have felt isolated in their youth. She didn't fit in while she was in college, so that helps her sympathize with Anna (and fall in love with Campbell… or she would if he would be honest about himself for once).
There are pictures of me, too, but not many. I go from infant to about ten years old in one fell swoop. (3.7.3)
Anna seems to suffer doubly from being both a genetic experiment and the youngest child. Her parents just don't care to document her childhood as much as they did with their other kids. No wonder Anna feels she doesn't exists—there's barely any physical evidence of her life.
I tell myself that I've invited [Duracell Dan] along to add to the thrill—one more person who knows only makes it more exciting. But it's really because there are some nights when you just want to know there's someone else besides you in this wide world. (5.4.9)
Poor Jesse is so lonely that he has to pay a homeless man (in Happy Meals) to accompany him on a truck-jacking. If only he lived in a world with meetup.com, he might not have as hard a time finding friendship. Alas, this is the 1990s.
"How the hell did Anna Fitzgerald slip through the cracks?" (7.2.78)
It's not just Anna's family who ignores her; the medical ethics committee, whose freaking job it is to analyze cases like these, didn't even notice Anna.
The summer I was fourteen my parents sent me to a boot camp on a farm. (7.4.1)
Jesse's parents' hearts are in the right place (or are they?) but this is bad parenting. He's acting out because he feels isolated from his family… so they isolate him more. Spoiler alert: It doesn't work.
I do what I know will destroy [Jesse]: I pull Jesse into my arms as he sobs. (7.5.42)
And here we go. Brian finally figures out the cure to fix his lonely children: Show them love. Hugs not drugs, y'all.