It didn't work out well to break the rules by which your temporary BF runs his life. Since you tolde his partner that he's having other girls besides you, it would seem that you realize your days are numbered with him, if not already over with. Being in love with him doesn't guarantee you anything from him, though it does signal him that he can keep contact with you and try to train you to play at sex and love according to his needs and rules, if he wants to risk your spoiling his home life again. If I were you I'd chalk this up to "live and learn," and start directing your energies toward getting over him. Unless you think there are more good lessons you could learn by trying to hang on and win him back.
But I find it hard to imagine that he'd want to take another chance on you ratting him out to the mother of his child again.
I understand that..but now when he started to talk to me, maybe i really have a little chance to return him? Otherwise, he would not have talked to me in front of all his colleagues, who know that he is with her..or he just want to be nice with me and move on?