Do I stay with him?

So I’ve been dating my boyfriend for about 4 months and just found out he got somebody pregnant around the time we started dating before we got serious. He found out a month ago that she was pregnant and I had to find out on my own from the girl, he said he was scared to tell me bc he didn’t want me to leave him. I love this man so much but don’t know how I can trust him again or if I want to stay in a relationship while he has a baby on the way with another woman. Help.