Dear MIMsters: Should I Leave Him or Continue with the Relationship?

I need some relationship advice as I am at a crossroads, not knowing whether to continue or quit this relationship with my boyfriend.

I am currently having a problem with my boyfriend who I started dating four months ago. Through his chats I found out that he has been cheating on me with other girls. They were about three of them and he professed love to all three of them. I confronted him and to silence me, he slapped me across the face.

I did not waste time before returning the slap. I slapped him back and hard and warned him never to talk to me again. Since then he has been apologising and begging me not to leave him. He’s been communicating with me through his friends because I have vehemently refused to pick any of his calls , respond to any of his messages or see him because of what he has done.

He is the one who cheated, yet he had the guts to slap me after I confronted him and reacted. His friends are telling me he has been sick and has been on medications since that day. Now, I am so confused as I don’t know if I should stick to my decision to leave him for good or forgive him continue with the relationship. How am I even sure who is his main chick and I am not the side chick. Please I need your advice.