What’s the difference between Xander’s AR and Spike’s AR?

In my opinion, the difference isn’t in the act of committing the AR or who’s more to blame for their actions in starting out doing it, it’s all in the act of stopping and what you do afterwards.

Xander stopped because the possession was broken.

Spike stopped because he realised what he was doing was wrong.

Xander used the possession as a reason to never have to talk about it again or accept that he might have been responsible in any way for it.

Spike went out and put in what he felt to be a needed barrier so that it wouldn’t happen again.

Both scenes show the argument that men are animals who cannot help themselves but rape. Xander is literally possessed by his animalistic nature until his “human” side is forcibly reasserted to control the urge. Spike inhabits his animalstic nature all the time because he’s a vampire, but he has a moment of realization of what he’s doing and stops himself. He’s easily stronger than Buffy, especially in her weakened state. He doesn’t have to stop.

Spike’s AR therefore suggests that the animalistic nature argument is full of crap. If a creature in a supposedly permanent thrall to its animalistic nature can stop, take responsibility for his actions and not want to commit rapes anymore then so can every man out there.

Spike was responsible, and he knew he was. He took the blame and the responsibility for stopping it happening ever again. That’s the damn whole point of him getting a soul.