Child In An 18 Year Old's Body

I was talking to a friend on AIM today. She told me that she and her boyfriend broke up today. Of course, I asked her why. Her answer was that they both couldn't take the fights anymore. But I have to say that the fight was a pretty reasonable fight. Not like those stupid fights couples get into then don't know why they fought by the end of the argument. I wouldn't say that the reason was "cheating," but I guess there were suspicions of cheating in the near future. I asked her, "Are the fights more important than the love?" She clearly said no. I thought that would have been the end of it and that she would have tried to get him back. But it wasn't. She told me that she did try to contact him. But he deleted her from myspace, changed his number, and broke off any communication to her. Sounds immature to me. I guess the reason for doing this was to "help her let go." Sure, hurting her will help her let go, but it there are other ways than to hurt, especially to do this to her. It makes me angry that he's 18 and he does this like he's still a child. I personally think that he should control his temptations because if he claims he's happy with her, then why would you need anyone else? She still loves him, and apparently, he still loves her. If that's true, why would you hurt yourself and the one that you love so you can both let go. What is there to let go? Fights are normal and when couples get through them, it shows a strength in the relationship. Giving up a relationship for a fight, to me, wasn't a worthwhile relationship to begin with.