fly on the wall
you have but-face.
It IS a fact that running away from her family and friends for months on end without calling once, was wrong. I mean come on? It WAS selfish because she put her mother through all that worry. How would you like it if your kid did that to you? It is irrelevent that she NEEDED to. If she wanted to take off then she should have called. No, this is not subjective, what she did was wrong. period.
A sentence that ends with "was wrong" is an opinion, actually. Not fact.
If my kid did that to me, I'd be hurt and angry and endlessly worried. If my mom said the things to me that Joyce said to Buffy, I'd be hurt and sad and I'd feel like I couldn't go home. If I went through all that Buffy went through that season, I'd probably would have run away too.
I just can't declare Buffy's actions as "wrong" because of the reasons behind them. If she had done that for no reason, yes, that would be wrong. But she had a boat-load of reasons that are entirely relevant. We can't just ignore the "why" here. I won't say what Buffy did was right. I will say it's something a lot of us probably would have done, and I will say I don't think it was wrong. There were better ways to handle the situation, but I don't think Buffy could see any other option at the time.