I've attempted suicide more than once, but the focus of it was never about being transgendered. This is mostly because I never admitted to myself that I was up until recently. My mindset, at the time, was that life had gotten so bad, and there was no hope of it ever getting any better, that it's better to not exist at all. Later when I was married, I was also thinking about how much I was holding my wife and son back, how much better they would be without me because I was such a poor excuse of a human being, and that they could go on to better things once I'm not longer there to weigh them down. These thoughts are not rational, much like how our transgendered thoughts are. Asking somebody who's suicidally depressed why they feel that way and why can't see that life is so much better is like asking us why can't we just live with the bodies we're born with and be happy? You just can't.
If you've never felt suicidal, then you've been blessed. It's not a point anybody enjoys getting to and if I could turn back time and never do those things I would.