How do you let go of the reins in your life?

I’m going through several different situations at the moment, where uncertainty and the unknown are two of the biggest factors. I do not handle these well. I feel like I need to think and think and think and think until I have a plan for every single possible (and some impossible) scenario that could occur. It’s become so natural for me that now I’m pretty sure I have an undiagnosed anxiety disorder.

Everyone in my life keeps telling me that it’s a completely unrealistic way of coping, and I know that. I just can’t stop.

Aside from a therapist, which I’m working on (try finding a good, trustworthy therapist with your ho-hum insurance!) has anyone discovered any techniques that work for them to just let things work their course naturally?