Sweetheart, you are with a liar and a cheat, a weak man at best, a cruel manipulator at worst. I would suggest this: every time you are tempted, think of that man's wife and child and how he is letting them down. Do you want him to do the same to you? For your own self-respect, you need to walk away, with dignity. I know too many women who have wasted their lives waiting for married men, only to be ditched when something younger and more tempting came along. Don't just try to forget him. FORGET HIM. You will be glad you did.