Today my friend from University told me that my ex who I dated for 3 months last year, was talking shit about me to about 12 people at my university at a party. When we dated, he cheated on me the entire time and I found out after he broke up with me (he said because he didn't want a serious relationship and didn't mention he was sleeping with other people.) I didn't cheat on him during the relationship. Why would someone do that? When we were together, I thought the relationship was nice and loving. He said I love you first and was the one to go after me. I really don't understand.