I'm just gonna say random things that came in to my head when I read your post, not sure if it's good advice though.

Can you be vulnerable with yourself? Like cry on your own, write devastating journal entries, watch yourself in a mirror until it's hard to make eye contact. Feel your own body. Be totally honest with yourself.

Then after practising that for a bit you take it to therapy, the therapist becomes sort of like a witness to your vulnerability... but you aren't doing it *for* them to see, you are just doing it for you.

Personally I build walls up and break them down, only to have new ones pop up because of something that happens or is said and then I have to do it all over again. So tired.