Are there such things as sexually deviant sleep disorders?

My best friend of 8 years has a new boyfriend. I flew in to visit on St. Patrick's day, we all got rip-roaring drunk and the 3 of us, me, my best friend, and her boyfriend crashed in her bed together. I woke up to find her boyfriend's arms around me and he grabbed my butt a few times. I knew it was odd but I was drunk so I fell back asleep and the next morning decided to let it go because I figured he was just drunk. The next night I went to sleep in my friend's bed and an hour later she came upstairs with her boyfriend and due to a shortage of beds, the two of them climbed in with me. Again, I woke up to find his hands on my stomach. I rolled over. His hands went for my butt and he tried to reach between my legs. I jerked and he moved his hands away. I didn't know what to do, just ignore it or tell my friend. He grabbed my breast and I grabbed his hand and told him to stop. Then I got up and went and slept downstairs on the couch. I told my friend the next day. She was very upset. I only recall what he did to me after I was awake; I hate to think about how far he got while I was sleeping. She broke up with him immediately, and was very upset. He has tried numerous times to get back together with her. He says he has a sleeping disorder and he wants her to contact his exes and some doctors to verify this. He says he sleepwalks and behaves sexually while he's sleeping and that he does not remember anything he did to me. So question is: is this guy a sexual deviant who gropes women in their sleep or a poor dude with a legitimate medical problem? Should she take him back?