I don't even feel alive.. I don't know if that makes sense but I don't even feel like the person I see in the mirror... I feel like a thought in someone's head... I feel like I'm not part of this family.

Just thinking of this makes ne feel tense and make my heart go fast

That sounds like maybe existential ocd? When I get really stressed I deal with a lot of depersonalization but exercise makes it so much better.