I think Eric was suicidal because besides hating the world and the way life operated, he felt he didn't belong here.He felt like nothing would ever change, he'd never find his place, he'd never find the right people who he could truly belong with.
He'd go through life like the misfit he somewhat was always searching, never finding, always frustrated and lonely.
Eric was a very angry individual but I think he was also a deeply lonely one. I've often had an imagined image of him staring out that small window in his room late at night when the whole neighborhood was silent and he was the only one awake probably for 5 miles around,looking into the black night sky and thinking of his loneliness and how he'd never find the things he was looking for and how hopeless life seemed to him.
I think those are the times he'd really let himself think about it.
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We're all going to die, all of us, what a circus; That alone should make us love each other but it doesn't. We are terrorized and flattened by trivialities, we are eaten up by nothing.-Charles Bukowski