Would you tell a girl that her boyfriend had cheated on her with you? I can't decide if it's girl code or just interfering in someone else's life.

I was in this situation a few months ago but I decided not to tell her.

Basically I saw my ex in a club, I never stopped loving him and we'd ended up talking all night and we did make out. He told me he had broken up with her and that he missed me and was jealous when he saw I posted pictures with my new boyfriend on instagram (I had just broken up with him). We left the club together, he begged me to go back to his place but I said no.

There was a few texts exchanged in the following days but nothing major. I saw on social media that he was still with his girlfriend. A few days later they announced that they were having a baby. I texted him saying congratulations but I have to admit it did hurt. I told him I wouldn't say anything but his friends knew because they saw us together in the club. I still think about him.

I still don't know if I made the right decision by not telling her but it was different once I realised a child was involved.

Has anyone been in a similar situation?