That suggests a couple more strategies that you could use for deciding-while-numb.

One is to choose the option that is most likely to improve your mental state (or at least avoid making it worse), e.g. the option that seems most likely to increase your energy rather than draining you.

The other is to try to make your decisions while non-numb, as much as possible (especially for more important decisions). You can do this in different ways, depending on the context. When you're numb you could put off making a decision until later (when you're non-numb), or you could guess what you would choose if you were non-numb, or you could try to remember which option you were leaning towards when you had been non-numb and choose that one. When you're non-numb, if you know of any upcoming decisions you could make the decisions right then (rather than waiting and potentially becoming numb), or you could at least note which option you're leaning towards (so that you can use that information if you happen to become numb).

I don't know the details of your experiences with doctors & therapists, but this really does sound like the sort of thing that they should be able to help with. Especially if you're in this state often, figuring out if you can prevent it should be a higher priority than figuring out how to cope with it. Maybe you just haven't taken the right test yet, or you haven't found the right doctor or therapist. If you've had horrible luck so far, does that mean that regression to the mean will be working in your favor as long as you keep trying?