He lies

We had been dating for two years..he working at one company..his position as marketing executive. I know he always with me everyday, everytime..every lilttle thing I want I'm sure he will fulfill my wish. But one day he ask me acting that we break up..let the whole world know it..he said because his boss dun like it when I'm always call him, text him at office. Alright..I agreed.after 1 month acting like that finally I found out that he is cheating on me. The girls I always talk actually is his new girlfriends. She call me & admit that they in relationship.OH NO. After I received the call, I call him too discuss bout this, first I relax..but when get in his car I'm crying & ask him to send me back at my home. He ask me why, I said your a liar. I told him everything..what sh said..what she ask to forget him & he said pls dun that. Before I goin back to home. He just said yes..I in relationship with her but this is to save my work..she is my boss daughter. But I dun love her..she just to called like my saver for my work.. I'm in bad situation when I can't either sale anything this few months..should I believe in him? We still together until know but the another problem is she still chasing him @ act like he really love her. What should I do:P