My ex-Boyfriend's best Buddy

I met my boyfriend at university, and we got on very well and I thought we had a future together. But that was shattered by him becoming violent towards me after we had become lovers. He tried to dominate me in what I wore or who I talked too and in just about everything other way. The last straw came when he went to strike for refusing his command. He was stopped by his best bud who wasn't regularly with us when we were out. He wasn't a university student and had to work to get by not like my boyfriend. My boyfriend told his buddy he had right to bash me as I was his and he could do what he wanted to me. I made up my mind I was finished with him and told him so, he again tried to hit me and was put on his ass by his buddy. He told his buddy they were thru and his now ex-buddy, said yes, we're thru and have been since I saw you try to hit her. As I walked away with the no ex-friend of my ex-boyfriend, my ex decided to attack us from behind and ended up back his ass again. He saw me home and left and my ex changed universities after as almost everyone had seen the incident. A month or so later I was at a demonstration of martial arts and one of the instructors was my ex's ex buddy. He was state and national champion, I took the chance to talk to him and became a student of his. Private student one on one instructions, not that sex was involved at first, but as I was with him more and more, we started to date and sleep together then married and now have 5 children.