I Can’t Trust him anymore

Dear Sis Dolly I have tried to forgive the man I’m in love with for sleeping with his colleague but the problem is I can’t trust him anymore, ever since the incident I have never found any closure to it and don’t see the importance of being in a relationship that I’m not happy in it, my problem is I have introduced him to my family and they love him but I can’t stay with him anymore.. Do I have to be with him because my family loves him or should I consider my happiness first?