When I'm feeling stressed, I don't sleep well. When I don't sleep well, things that would ordinarily not bother me, do. It's a vicious circle. I've been trying different things to help alleviate stress -- exercising, writing in a journal, meditating (which doesn't work for me because I have a hard time quieting my mind).
A couple of weeks ago I came upon an article in a magazine that told how celebrities managed their stress. (Yes, I hear you all laughing right now. What stress could they possibly have? At least that was my first thought.) One model stated she'd developed the attitude that whatever the thing was that was causing stress wasn't worth her time, her energy, or her sanity. Something about that rang true with me.
So now when I'm feeling stressed about something that's beyond my control or that I can't do anything to change, I tell myself, "It's not worth my time. It's not worth my energy. It's not worth my sanity. Let it go." Sometimes it's easy to do, other times not so much, and sometimes I find myself saying it multiple times a day about different things. Strangely enough, it seems to be helping me sleep at night. Try it and see if it works for you.