I have a similar thing that I've been unsure how to handle.

About 6 years ago I had just gotten divorced... I was seeing a new girl who was obsessed with getting married. I told her I wasn't interested even a little bit in being married ever.

She seemed to believe I was in love with my ex and that's why I said that. I think she had an issue with an ex who left her for his ex wife. Anyways... we broke up. About a month or two later I see on Facebook she is engaged and now pregnant.

I asked her if it was mine and she said no. She told me she was pregnant before we started dating and didn't know. (We were only together a few weeks) I calculated the kid should be born in April if he was mine...

So in about January or February her engagement ends... I asked her why and she said that guy didn't believe it was his baby and he left. I asked her again if it was my baby and this time she said "I don't know. It doesn't matter I'll handle it" so I said if that baby is born in April we should talk.

Kid is born in April. I reach out to her a few times, but she says it's not mine again and continues with her life. By end of April she started dating a marine. By August they were married and he adopted the boy.

When he was about 3 or 4 she finally messaged me and said he was mine and she wanted to get back together or something. I freaked out on her a bit because she named her son after a Nicholas cage movie character and I didn't want to introduce my son Nicholas cage to people because what kind of moron would name their kid that. Anyways she got upset I was upset and made up with her husband. The kid is now 5 I think. They are still married and I have no right to call myself his dad. I doubt the kid will ever know... but i really wish I would have been his dad.