That sort of happened to me too... I have no idea why, nothing really changed except my mood probably. But I spent years researching methods and a year trying partial hanging - I had the sheets tied up as a noose permanently so I could keep trying and practicing for 8 months. I never got my carotid artery though just exploding head jugular and very painful. Then I was trying to find a partner online and I found one that I was talking to, he was located a ferry ride away, but for some reason I stopped responding. It was at that time I felt like I wanted to stick around and do something, I was motivated, and completely did a 180 and cleaned up my living space (it was a horrible dump) and got on methadone. I gave life another shot but then I started thinking and watching others, watching the world, I got involved with animals and rescuing... and it just made me feel awful about life, because of how much suffering there is. In the 3 years that I was doing well I always wanted to die, I would have accepted my death if it was an accident, but I wasn't actively suicidal. After so many disappointments and one thing after another, I became depressed and angry again. I think my issue is more philosophical than mental or moody...
I just feel like life is a horrible curse and I can't bear to live with knowing how badly animals and other living things are suffering, children, and even people even though I'm a misanthrope. I'm just really not interested in sticking around, my own personal life is horrible too I live in a very abusive household which I can't escape, ctb is literally the only way out believe me I've gone over it a hundred times. The only way I'd ever stick around for a little longer is if I won the lottery, then I could easily ignore everything and everyone and buy N and ctb before I get old and crippled. Life is filled with constant suffering and it's totally pointless, we all die in the end and there's so many people in the world that our individual lives don't matter at all. So why endure all that suffering for no reason?
There's a million reasons why I think life is terrible and only a few reasons why it's amazing, and unfortunately we're too busy trying to survive we barely get to feel the amazing things or see them. If I won a ton of money to buy freedom, I'd stick around just to see the world and what happens in the next 20 years. Like an audience watching, instead of the actors playing and suffering so much.