It's like a prison

I think I might be driving myself crazy. I really really do.I feel so trapped in my thoughts.

The same things, everyday, back and forth, over and over again. And then they're contradictory, and then it's right back to where I started.

It's a constant struggle. A fight I may not win. I'm confused. I'm stuck.
And then there's nothing.
Why does it always have to happen like this. I always have to second guess a decision I was sure I was confident in, 100%.
More than one decision. It's like, as soon as I'm second guessing myself in one area, I have to go and re-evaluate and second guess another.
I can't just let myself be happy. Maybe because I'm not entirely sure I am? I don't know.
I'm trying. But that's all I can do for right now..