Most Helpful Guy
Be straight if you really can not stand for this relationship and your mind is sure about him, just tell him that you are not getting comfortable with hims because of this or that reason. It might be possible that he can change himself for you, if not you can let him go. But if there are other reasons too, so let him know and make it clear. Because ones you leave him without clearing the facts, he can talk to common friends about it and he can put all the blame and responsibilities of break up on you. There won't be any problem to tell him about this. For a good future it is necessary taking straight steps and telling the truth at least to your partner. You can do one thing also send him a mail and right down everything why you are doing all this and ask him for his reply on mail only.