SUBREDDIT: r/relationships
TITLE: [19F] My Boyfriend [19M] Broke Up With Me For Something That Happened Long Time Ago
POST: About two months into our relationship I cheated, I slept with another guy but there were no feelings involved and it was a one time thing. It ate away at me throughout our entire relationship and I've always felt guilty about it. Now we've been together for nearly a year and a half, and I finally told him because I couldn't deal with the guilt anymore and I knew it would always be in the back of my mind. I told him I needed to speak to him about something that happened a long time ago, I got him to promise he wouldn't break up with me over it, but he did break up with me right after I told him, and I've been trying to text and call him but he's ignoring me and I don't know how I can get him to stay with me. I feel like it's kind of a slap in the face that after a year and a half of being together he's going to leave me over something that happened so early into out relationship. I really don't want to break up.
TL;DR: 
I just came clean to my boyfriend about cheating on him early on in out relationship, he broke up with me. I don't want to break up, but now he's ignoring me.