I believe that as Poet is waking up to this all, she is increasingly less able to tolerate the abuse. Just look at how she has been able to state her boundaries and also recognise what he is doing - ie the staying quiet and then asking him if anything happened, to test if he would be honest, the watching from inside herself as he forced her legs open, and the recognition that yes, he is a bastard.
There is a push pull between us and the therapist, and her husband tunring on the charm, or pulling out the emotional guilt trip to reel her in. As Otterly said (I think) he is an expert at those words and they seem to provide a cloud of warm fuzzy hopefullness over the truth that she knows for a while.
I suspect that as she starts to see the truth, she is also less able to cope with the abuse, which makes it harder day to day, so the pull of his mealy words is greater, in a way. But also I would suspect that her body is also on a higher alert. My suspicion is yes, he did start to touch her again, and her mind, fresh from the danger alert of the therapist, sent her into a panic. Especially if she was in a deep REM sleep - it could be really vivid - so waking up sweating and shaking to a nightmare is likely to be triggered by something. You say you regularly wake up quickly - Im not sure that is so normal. Ive been tracking my sleep as I have sleep apnoea and use a CPAP machine, and have been learning how to use it and how to adjust settings, etc. I wake up quickly if I have a series of events (where I dont breathe for 10 seconds or longer at a time, and my brain thinks Im dying) when Im not having events I cycle gently through different stages, up and down, and only briefly awake and asleep. Also the sleep bits of apple watches and wearables is not very accurate at all apparently.
If you are waking up rapidly there is usually something happening that makes you do so. A baby crying. You cant breathe. Something has disturbed you. My belief is that it is him. He needs you to be in a deep sleep, and you were not.
My bets are also on Poets husband actually holding out for a week or more. I think he knows that his chips could be fried, and he is going to pull it out of the bag to get things back to where he wants them. A week or so of trying SOOOOOO hard, look at him, poor boy, performatively taking himself to the sofa, and asking her how she is all the time, MIGHT be enough to get next weeks therapy cancelled and her to believe that everything is all good with them. How much love bombing will that take. I think next weeks session could be crunch time. Its all getting a bit real for him, and he risks losing what he has got here. If she carries on going then it could start to get nasty.(nastier) because he will start to panic.