Ideas for boundaries?

Sometimes I can hardly believe I’ve only been doing this course for 6 weeks. The content and work I’m doing is seriously life changing!
So my husband drinks a lot and although it (aka my thoughts about it) has caused me a lot of frustration and pain in the past, I want to stay with him and I want to accept him as he is. I have started to recognise that his drinking has nothing to do with me and there are very few negative consequences from his drinking (i.e. his personality doesn’t change while drinking, he’s still very kind to me etc).
The one negative consequence is that after he drinks he sleepwalks. I used to get up and panic and try and help him / stop him doing anything bad but have let go of that a while ago now, which serves me.
The problem is his sleep walking does wake me up and then I struggle to get back to sleep. I’m not sure how to set a boundary about my disrupted sleep? Our house has noisy floorboards so I can’t actually sleep in another room to not be woken by him. Any ideas on a boundary that helps me separate from this circumstance? Thanks!