i keep dissociating during full swap and i dont know if its the swap thats wrong or if its something older

this is going to be hard to write coherently bc its still half formed in my head. im 36, husband is 39, married 8 yrs, in the LS just under 2 yrs, leeds. soft swap was great for the first 18 months. moved to full swap about 4 months ago, both of us agreed, both of us said we were ready. weve done it 5 times now. and every single time, at some point during the actual penetrative bit, i go away. not in a sexy "lost in it" way. in a clinical "im on the ceiling looking at my body" way. my mind detaches and watches. i carry on functionally — moving, sounds, the bits u do when ur having sex — but the person doing it isnt me, im upstairs watching her do it. once we're done and back together with my husband im back in my body almost immediately. the whole thing folds back in. i feel normal. i sleep fine. the next day im fine. its specifically and only the full swap bit, and specifically the penetration part, that does it. soft swap doesnt. play with my husband doesnt. anything else doesnt. ive talked to my therapist (yes i have one, this isnt my first rodeo with my own head). she said this is "peri-traumatic dissociation" or possibly just a high-arousal state thats expressing as dissociation in someone with my history (i had a difficult time in my early 20s, complicated stuff with a long term partner i wont go into but it left marks). she said the question isnt "what is wrong with u" the question is "what is ur body protecting u from" and we've been working on that. here's what im sitting with. its not unpleasant in the moment. its actually quite peaceful in a weird way. but its not real intimacy and im not actually present and i dont think it's ok to keep doing a thing where i exit my own body 5 out of 5 times. my husband doesnt know yet. ive been telling myself "ill bring it up after one more time when i have more data" which is itself probably a dissociative move now i think about it. ppl who've experienced dissociation in LS settings — does it pass with more experience or is it a sign to step back. did u tell ur partner. did u stay in the scene with a different shape (eg back to soft swap only). is there a version of the LS that works for ppl with dissociation tendencies or are some of us better off in other configurations