Stop imagining what isn’t there.
If you’re thinking more than one step ahead, stop. Controversial advice I know. Probably not as helpful if you’re flying a plane or some such thing. However, for everything else that’s going on in your head, if you’re worrying about the what ifs, most of that worry will be for nothing. Even if it happens, it will never happen in exactly the way you imagined so you will never react exactly the way you planned. Take a conscious step in the direction you want to go, and learn to trust that you will supported in the next one.