I completely relate and recently I've written several letters to various people explaining why I did it. To be delivered after. Still here. Letters are still on my computer to be printed. Maybe.
It did help me to get them written because, as you said, it helped me clarify my thinking about why I'm thinking this way. I'm really good at rationalizing things, even when I know my thinking is broken and I'm in no position to make good decisions about my life. I can easily convince myself that it's a bad idea or it's a good idea. I hate that I've dealt with all of this for so long that I can convince myself of anything and then also not believe a word I say.