I'm no doctor or expert and i mean no offense but i do have to say that I've seen a lot of weird things in peoples sleeping and i don't understand why he finds this disrespectful or why he feels inadequate, its something you cannot control or have knowledge of. Also I think that he should believe you if he trusts you enough to be in a relationship where you're sleeping together. I know my girlfriend means no harm or disrespect when she says mean things in her sleep, because the next day I'll say something about it and she'll have no memory of it just like you touching your self. My girlfriend walks, talks, eats, drinks, and does a lot of other things in her sleep that i know she can not help just like you cant help it, i don't know if there is anything that can be done about it, but i think your just going to have to explain to him that its not something you can help and that he's just going to have to get used to it. If he cares about you enough to sleep with you then it should not bother him that you do things that you cant even control.