I don't think I ever felt sorry for Xander other than he had crappy parents.
Oh, I always feel bad for poor Xander. When he lost his eye, when Buffy rejected him, when Buffy humiliated him with the sexy dance, whenever Giles yelled at him and he looked like a kicked puppy, when Cordelia told him he was useless in the Zeppo, when his friends started neglecting him in S4..... etc.
I wish Xander and Willow would have had a conversation about how they didn't want to become their parents at some point; it seemed like something they would of had in common.
Where is the line between feeling sorry for someone and blaming their parents, and blaming the adult themselves for their actions?
I think it comes down to the age old question - How much of someones actions can you blame on their past? I'll also cut straight to the chase and bring up the obvious further step with what you are saying. A young man has an abusive father and he ends up being Adolf Hitler, how much of what Hitler did can you blame on his authoritarian father and the constant emotional and physical abuse that he received in his young years?
I'm not making a comparison to Xander and Hitler at all, just voicing the question. Where is the line between feeling sorry for someone and blaming their parents, and blaming the adult themselves for their actions?