Hi ArtGrey, welcome to PC sweety!
I'm sorry that you are going through all this, and no one here can really diagnose you hun. We can relate though and hope you find your answers. Are you seeing a therapist?
I get what your saying, I think. I hate looking at mirrors. Every now and then after life changes, I'd take stock in the mirror and evaluate what I know and saw. I've always felt a disconnect with my reflection as if it were someone else (because it was). I'd get spacey, lose a sense of self, and just observe, silently. Being with other people made it worse for me because I didn't know how to cope with others.
I've had a lifetime of identity crisis, even genderly. I've grown to unbelievingly accept the mirrored image because of these past 47 years, the reflection hasn't changed much (sigh).
Other times that I'm triggered is when I'm having an emotional breakdown through psychosis. I get so stressed with my anxiety peaking, I feel so out of body watching myself walk, talk or rant. This is usually at a crisis moment on the verge of self destruction. I'll have a switch where another personality takes over to bring me out of it, thus saving myself.
Talk therapy and learning grounding techniques should help keep you reeled in. Sometimes I got to literally pinch myself a few times to get the body feeling back. I hope you find your answers sweety!