i have been in your situation. the best thing i ever did in that relationship was tell him that it was over. i was straight with him. tell him exactly how you feel. there is nothing more freeing about breaking up than saying exactly how you feel and ending the relationship. if you are not straight with him, than you could be going down a road that you don't want to travel. it could drag the relationship on for an unnecessary about of time.
there is no advice better than honest communication. you do not deserve to be treated disrespectfully. show that man no mercy!!!