I need to make my fiance miss me and feel lost without me.. So he can change.. Help?

So basically Ive been with Edgar for 2 years. I love him. Theres no doubt about that. I am very hurt by so many things hes done. I know the best thing to do would be to leave him. But I cant imagine my life without him. I JUST WANT HIM TO CHANGE! Hes cheated. Hes lied. He had a child with a girl he cheated on me with. He talks to his friends about hooking up with other girls. Its so wrong. PLEASE DONT JUDGE ME. Okay so here it goes. After many talks and many threats to leave him, I found in his phone yesterday him talking to his friend about having a three-some with some girl. and also about hooking up with some random girls from Chico. He tried to tell me that its just how him and his friends talk but he wouldnt do it.. how stupid does he think I am.. Well i want to make him miss me like hell and fight for me so bad... I want him to hurt.... What should I do... ???? Help me. Be creative.