We've been together four months and he just told me that his ex found out that she's pregnant😧 I am shocked and saddened at this news. He's not sure the baby is his but his ex seems certain that he's the father. He suggested abortion but she's not receptive to that. She gave him the option of not being involved with no strings attached but he's a stand up guy so he wouldn't do that. 

Since this news, he's expressed to me, with sincerity, how much he cares for me and how much he doesn't want to lose me because of this. He sees potential in our relationship because of our chemistry and how well we complement each other. 

I am at a loss right now, I don't know what to do. Dating a guy with a kid was a dealbreaker for me because of bad past experiences, but in every other aspect this man is great.

What would you do in this situation? Would you stay and wait it out to see if the baby is his, leave now and not look back, or dealt with it?