"Oh, sir, if you know who this man is," cried D’Artagnan, "tell me who he is, and whence he is. I will then release you from all your promises--even that of procuring my admission into the Musketeers; for before everything, I wish to avenge myself."
"Beware, young man!" cried Tréville. "If you see him coming on one side of the street, pass by on the other. Do not cast yourself against such a rock; he would break you like glass."
"That will not prevent me," replied D’Artagnan, "if ever I find him." (3.71 – 3.773)
D’Artagnan is not to be deterred from taking his revenge. This is evidence of his foolhardy nature.
Unfortunately for D’Artagnan, among the spectators was one of his Eminence’s Guardsmen, who, still irritated by the defeat of his companions, which had happened only the day before, had promised himself to seize the first opportunity of avenging it. He believed this opportunity was now come and addressed his neighbor: "It is not astonishing that that young man should be afraid of a ball, for he is doubtless a Musketeer apprentice." (7.52)
These cycles of revenge are what lead to constant warfare. No wonder everyone is always fighting in Paris at this time.
"Yes. The Cardinal, as it appears, pursues he and persecutes her more than ever. He cannot pardon her the history of the Saraband. You know the history of the Saraband?"
"Pardieu! Know it!" replied D’Artagnan, who knew nothing about it, but who wished to appear to know everything that was going on.
"So that now it is no longer hatred, but vengeance." (8.50 – 8.52)
After his declarations of love are scorned by the Queen, the Cardinal is out to get revenge. This is a bit unfair to the Queen, seeing as she has barely any power.
"No, Kitty, you are mistaken. I do not love her, but I will avenge myself for her contempt."
"Oh, yes, I know what sort of vengeance! You told me that!"
"What matters it to you, Kitty? You know it is you alone whom I love."
"How can I know that?"
"By the scorn I will throw upon her." (33.122 – 33.126)
Here D’Artagnan is trying to persuade himself and Kitty that he feels nothing for Milady, but rather that he is motivated to act in order to get revenge.
"No, I do not hesitate; God forbid! But would it be just to allow me to go to a possible death without having given me at least something more than hope?"
Milady answered by a glance which said, "Is that all?--speak, then." And then accompanying the glance with explanatory words, "That is but too just," said she, tenderly. (36.119 – 36.120)
First of all, D’Artagnan is basically asking for sex. Milady tells him yes, he can have that. She clearly has no qualms using sex in order to achieve her goal of revenge against the Comte de Wardes.
D’Artagnan, on his part, had gained the summit of all his wishes. It was no longer a rival who was beloved; it was himself who was apparently beloved. A secret voice whispered to him, at the bottom of his heart, that he was but an instrument of vengeance, that he was only caressed till he had given death; but pride, but self-love, but madness silenced this voice and stifled its murmurs. And then our Gascon, with that large quantity of conceit which we know he possessed, compared himself with De Wardes, and asked himself why, after all, he should not be beloved for himself? (37.8)
D’Artagnan is perfectly aware that Milady is manipulating him in order to achieve of her goal of avenging herself on the Comte de Wardes, but he cannot help but feel persuaded that she really does love him.
Richelieu, as everyone knows, had loved the queen. Was this love a simple political affair, or was it naturally one of those profound passions, which Anne of Austria inspired in those who approached her? That we are not able to say; but at all events, we have seen, by the anterior developments of this story, that Buckingham had the advantage over him, and in two or three circumstances, particularly that of the diamond studs, had, thanks to the devotedness of the three musketeers and the courage and conduct of D’Artagnan, cruelly mystified him.
It was, then, Richelieu’s object, not only to get rid of an enemy of France, but to avenge himself on a rival; but this vengeance must be grand and striking and worthy in every way of a man who held in his hand, as his weapon for combat, the forces of a kingdom. (41.10 – 41.11)
Cardinal Richelieu’s motivation for winning the war is so he can show himself to be a better man than the Duke of Buckingham. Although it is Queen Anne inspiring such events, she herself has very little power.
"Look you, my friends!" cried D’Artagnan, "a horrible suspicion crosses my mind! Can this be another vengeance of that woman?" (42.49)
You really don’t want to get on Milady’s bad side. Her power and her cunning are very great.
The four friends, during the period of these two absences, had, as may well be supposed, the eye on the watch, the nose to the wind, and the ear on the hark. Their days were passed in endeavoring to catch all that was said, in observing the proceeding of the cardinal, and in looking out for all the couriers who arrived. More than once an involuntary trembling seized them when called upon for some unexpected service. They had, besides, to look constantly to their own proper safety; Milday was a phantom which, when it had once appeared to people, did not allow them to sleep very quietly. (48.117)
In her brazen efforts to avenge herself of D’Artagnan, Milady has the four friends psychologically terrified.
She rather feared that her preceding operations in England might have been discovered. Buckingham might have guessed that it was she who had cut off the two studs, and avenge himself for that little treachery; but Buckingham was incapable of going to any excess against a woman, particularly if that woman was supposed to have acted from a feeling of jealousy. (50.2)
Milady understands that Buckingham would never avenge himself upon a woman, especially if that woman was said to be acting due to jealousy.