How would you handle this..relationship issue ? males and females please.?

I have been seeing my bf for a little while now , we are both going through a divorce and neither of them are final yet. We both have a lot of common friends but had never met until right before we started seeing each other. I am pretty sure that he is looking for the old familiarity he had with his wife , but i am not her . He works out of town most of the week and is home on weekends , which he usually spends here . He called me lastnight and said his car was messed up and they couldnt get the part until today so he wouldnt be home lastnight , then he called later and i could hear people in the background and he said he was hanging out with some friends, He called back later again and asked me if i would have a 3 some...I played along for a while just to see how far he would take it and if he was serious..turns out he wants to have one with one of our common female friends..when I mentioned it later he said he was drinking ( i was told he was working on the car) and wasnt thinking clearly , but he kept bringing it up. He also told me he would be hom first thing this morning and its 11 am here and guess what , no sign of him other than a text at 8 this morning that says good morning..i asked what he was upto and when hed be home....no reply He tells me all the time that he loves me and that he is a one woman man and that I mean everything to him , but to be honest i dont believe him , I am curious about the psychology behind this ..and also wondering if I should end it. Any help would be appreciated.