Name changed for privacy.
I'm 48, and take a weekly acting/drama class just as a hobby. I am in a class of 20 people and one of them, R, joined because he'd had a stroke a few years ago and had been told that it would be good for his speech and mobility recovery. He's a nice chap, I'm really glad he's able to do something he enjoys and that seems to be be helping him. Scenes with him always go differently than planned as he has some mental cognition impairments to do with the stroke, as well as physical and speech impediments. The teacher and all of us are really supportive, cheering him on and I'm so pleased that in the time I've known him I've seen it make a positive impact on him.
Can you feel the "But" coming?
The class has a blanket no-touch rule. It's not necessary for anybody to touch another actor in a scene and it just keeps things not awkward.
At the end of year show last year, he accidentally grabbed my breast, hard, on two separate occasions 
I say accidentally because I do believe it was accidental, though the second time I was like really?? it was on stage, in front of an audience, the first time I just mentally brushed it off and I don't think he even noticed 
the second he definitely did and was highly embarrassed and profusely apologetic. I think both times he'd gone to put his hands on my shoulder (still not allowed) and missed 
it's inkeeping with other motor control things I've seen from him, like he'll go to put his hands on the back of a chair to steady himself while sitting down, and miss.
Since then I've seen him touch other people on the shoulder or back, and he's done it to me a couple of times again too. The teacher had a word with him about remembering it was no touch. Last night he touched three of us, all women, on the shoulder or back. I'm getting nervous about doing work with him. That scene he was particularly troubled by his symptoms, couldn't get words out, couldn't think of the next line etc, so I've no doubt it was logical to him to physically tell me to move (his line was to verbally tell me to kneel) because he couldn't get his words out, and was painfully embarrassed. Again, really supportive teacher (and I) helped him. Another, less awkward for R time and I'm sure our teacher might have reminded no touch, or I would have done.
I'm certain it's not deliberate or even careless, it's his difficulty retaining multiple threads of information in his head that causes him to forget not to touch.
Am I being unreasonable in feeling uncomfortable? Im unsure how to handle it. I'm considering having a private word with the teacher and asking to just not be paired with R, and explain what happened and it's similarity to what's still happening. I desperately don't want R to have to be told again and for him to feel awkward or be chucked out of the class or anything, I'm fully supportive of him being there and I'm very grateful he has such a lovely patient and supportive teacher and classmates. But my boundaries matter too, don't they? I don't want to be touched in class, and following my unfortunate experience with him I particularly don't want to be touched by him in particular and risk the same thing happening again.
How would you handle it sensitively?