My so called boyfriend has cheated on me

I was in a relationship with a guy since Feb 2010. Since Feb 2014 we are in a long distance relationship and we never cheated each other. We had physical relationship throughout our relationship. We decided that we will get married to each other and we spoke to our parents. Our parents were taking their own time to decide since it was inter caste marriage. But on 30th Sep he broke the news that his parents has fixed his marriage somewhere else and now he has moved on. I have always told him that I am damn serious about our relationship and will never marry someone else. But he has moved on very happily. He said that his family forced him to marry someone else and he was left with no other option other than saying yes to another girl. To me it looks like matter of dowry because my boyfriend once told me that his parents will ask for dowry for which I said big no. Another reason looks like my health condition because I underwent spine surgery in Nov, 2019 and doc informed me that I will face lot of difficulties in future once I get married. I did shared all these details with my boyfriend. It seems that my boyfriend never loved me and he was using me for his needs.