My friend has been touching me, and im confused ...help!

My friend and I are both quite close, both good friends and we talk alot. At this point I shall mention we are BOTH MALES, as here is where it gets confused:
He has recently been touching me in a sexual way as if to arouse me, and well... it worked. We have cuddled in public while around friends, he has sat on me and ignored the fact I was ‘standing to attention‘ until after he had finished his conversation, he has even rubbed my inner thigh (where my **** usually sits) with his foot, and even rubbed his ‘inner thigh‘ against my knee/leg; it‘s almost as if he is trying to get me(/us) going(/aroused).
I dont know what to do as he remains adamant that he is straight (he has a girlfriend (bummer)). I have told him once before to stop touching me if he is straight. Yet after a short while he started again, this time however I told him I liked him and that he should stop if he isnt trying to get me off (because I would end up doing something I might regret later). So far he has stopped, however it hasnt really been long (maybe a day or so) since I told him and I havent seen him much since then either.
So I guess my question is really: do you think he is gay/bi/bicurious but has yet to come to terms with it or is he doing it for the thrill of doing something he shouldnt (touching another guy in a public place knowing he is getting horny)? Or if you think differently please post as I really am confused and quite upset after being told it will not happen (I knew this anyway, but to be told it face to face is still devastating, especially after all the confusing signs/actions)!