I realize everyone has bad spots in life, even the rich and successful. Losing a friend is painful, no matter much good fortune you have. And it's natural to say you're still committed to life, even though you miss your friend. I'm probably "Sperging out" on Nicky Wire's lyric and taking it too literally, but to say you're committed to life no matter how miserable it gets seems illogical. I'm thinking that life has the potential to get extremely miserable, and that any commitment to life should (logically) be provisional. You have to be able to say "feck this, I'm outta here" at some point when a commitment to living would only mean more suffering.
People who categorically deny that option to themselves, whether for religious or poetic reasons, seem odd to me. For the ancient Romans and the imperial Japanese, suicide was considered a noble response to life and its various miseries. Suicide has poetry to it just as living does. I don't know enough about Nicky Wire to speculate on his depth of character. I'll just say I'm more on Morrissey's wavelength: "if you're gonna live, then live, don't talk about it | If you're gonna kill yourself, then for God's sake, just kill yourself."
I think I really am that simple. Because Amis was speaking in one of two ways. He was either loving life more in the abstract, or he was loving life more in the moment. The abstract seems wrong. He wouldn't think to himself, "I used to give life a 9, but now I'll give it a 9.5." Surely not with his friend gone. Life minus your friend cannot be better than life with your friend, all other things being equal. So he must've been loving life in the moment: "putting more into it and getting more out of it," so to speak. Which is a luxury the Martin Amises of the world have and others don't. That's why it seems like goo-goo to me. We are definitely on opposite poles of this one.