What should I do..., .. Options

[literemix24]

Okay, this isn't about me, its about my friend. One of my best guy friends, lets call him Phil, he's going out with one of my "old" friends. Phil and my old friend have been going out for about a week. At first it was really sweet and all, he walked her home and held hands and all that. Anyway, but somehow lately the relationship has been going haywire (the past two days). Phil is going suicidal, and he was starting to cut. Today, in our talent class, I saw him picking at his cut, and the day before he kept on cutting his skin w/ a pen, his flesh was sorta raw. Then at lunch, he went over to my old friend's table, and they started talking. Then suddenly he got provoked to walk over to the door and punch the glass. The glass cracked, and I heard from a teacher, that the window was supposively "unbreakable", also, the glass pane had wires embedded into it. Somehow, he broke through it, and yes REALLY broke through it, there were shards of glass in his hand. My old friend had wanted to break up with him on that day, but she hadn't brought it up yet. She was going to get back w/ her former flame. So should she break up with him? Personally I don't know what to do, and shes asking for advice. I don't think she should break up with him yet, at least not until hes stable enough.