Okay, Mibbians, I Need Your Opinions [On Writing and Characters]

I've been working on a book I plan to publish for a while now, and I basically have everything figured out except this one little thing...
I want to kill off one of my characters, with suicide.

But the issue is, I don't know what should set him off :/ I'll give you guys a little back-story/info on him and maybe you could give me some ideas?
My character is Max, he's 13 and he hasn't really figured himself out yet. He has low self-esteem and therefore social anxiety. Max loves his mother, but he mostly looks up to his dad. His dad works a lot since they moved to a new state and now every time he comes home, him and Max's mother end up fighting. He tries to calm it down and fix things, but it never seems to work, so he mainly just pulls his dad away when he can and spends the little time he gets with him.

Max has an older sister, and she constantly pushes him to be stronger, but it's hard for him due to family issues, no one to talk to, and the fact he is hard enough on himself.
Max has feelings for a guy he sees around school, a guy around the age of 19 or so. And he feels bad about it, but he can't help it. This guy he likes is a rich kid, dabbles in just about anything; a supplier to criminals and what have you. Well, this guy ends up talking to him and taking a liking to him. After him and Max spend a little time together, the guy convinces him to have sex with him. Max worries about if he was good enough, but never voices it.

And that's where what I know ends, what do you think this kind of rich kid could do to make Max kill himself the next day? I don't want it to be just Max convincing himself he wasn't good enough and never will be. What do you think could happen to bring Max to the brink? I mean, he finally got some happiness, any ideas?