Dear MIMsters: Will I be overreacting if I end this relationship with this man?

I met this man years ago who wanted a relationship with me then but I was in another committed relationship at that time. He was also going to the seminary. So I continued with this relationship that ended after it produced a baby.

Now this guy was rejected from the seminary after 7 years and he came to propose to me. I told him that we should date first for a while before we get married so I could get to know him better. The problem is I found out in June last year that the guy has been chatting with my sister who he has never met without my knowledge. He was trying to convince her that they have met. I asked him afterwards, he denied it at first but later admitted and said that his intentions were clean.

He came to Kenya a month ago from South Africa where he was studying and before he even told me he was around, he had already told my sister and requested her to meet him but she declined. It was after hat he called me. When I found out from my sister, I asked him but he denied it and accused me of being too protective of my sister.

Since that time, he hasn’t contacted me neither have I contacted him. I am thinking of official ending the relationship cause I feel he is not straight. Do you think I am overreacting?