I was in a very similar situation not long ago, just a couple of weeks ago, actually; I am living with my girlfriend now, and I had found her father's rifle in the basement -- with ammunition, to boot! It was very tempting, very, very tempting, and I woke up every morning thinking about it.
I mean, everything in my life was just so overwhelming, so seemingly irreparable, that I considered creeping down into the basement early in the morning when everyone else was sleeping, sticking that barrel into my mouth, tilting my head back, and just spraying my brains all over the ceiling.
I then thought about a more peaceful, less messy way to go, and, of course heroin came to mind; I'm not sure why I hadn't thought of overdosing on heroin first, as, you know, I'm a fucking heroin addict!
But, there's a documentary that I once watched and I can't help thinking about it every time I contemplate suicide. It's called 'The Bridge,' and you can probably find it on YouTube, albeit segmented into a million different parts.
It's about all of the people who throw themselves off of the golden gate bridge each year, and there's an interview with this one kid who survived. He talks about how it happened, and all of the thoughts that went through his head after he jumped and was falling... it's pretty unbelievable. His outlook on life is so radically different now, and it's just very thought-provoking.
I wish I had more to say, but I'll let everyone else give you the run-down on why life is worth living and all of that because, to be honest, I'm not sure myself. But I would definitely check out that documentary if I were you. The kid's story is amazing...