lmao, you can't put a spoiler in a thread title. that's just silly. and writing spoiler before it doesn't help because everyone is inevitably going to read the entire title. :-P
Ignoring the stupidity of this inability to make spoiler points...
Of course he died. He was about a foot away from the guy who blew himself up. But even if this had not blatantly, logically happened, you should still know that he died because symbolically, he'd been fulfilled in life, because he found someone he related to and didn't loathe. With his inability to love and be loved and his inherent talentlessness, his absolution with Sally was what was necessary to complete him, so from an existentialist perspective, that was all that was necessary, and he didn't need to live any longer.