Cheat or do not cheap

I need help. I have a ex boyfriend best friend, and once we had a sex experience for about 4 days, than I met my boyfriend and never went to.see him again. I got back to.talk to him last week and I went to his.house watch a movie, we almost kissed but I left, he is now dating but he said he is still into me. He asked me.to go to his house again to.watch a movie. I want to go because I love him as a friend. But I'm super into have sex with him, but I love my boyfriend so much. It's been 1 month since I last saw my boyfriend. And I am out of sex this whole time. Help me to get through this temptation pleease.