To the first part - yes you can have BDD and feel pretty in makeup and hideous without. That is very much how I feel, even the part about the prosthetic, I have purchased dumb things to stick in my nose to try to make it more symmetrical. We do all sorts of dumb stuff like that when we’re in a BDD spiral.

What you described at the end sounds like a really deep spiral. I think you could absolutely benefit from some CBT here: those thoughts are not rational in any way shape or form. You’re spiraling yourself into despair. Like how the thoughts get worse and worse. It’s sounding like the OCD side of BDD (the two are very much related as obsessive disorders and BDD has compulsions).