What would you do? *upset

Hi ladies

I split with my ex when I was pregnant, I walked away it just wasn't working out and the stress was too much to cope with. It was the best decision.

The babies here now he's a few months old. He hasn't seen the baby since he was born but it is going through the courts at the moment to arrange access.

I have just found out he has been seeing someone else. After checking her social media (I know, I couldn't help myself) I found he has been seeing her immediately after we split, when I was still pregnant. That hurts a little.

I saw that she had put a post up with her daughters name and my sons name written on a canvas and tagged his family in it.

I was fuming! Am I overreacting?

How dare she indirectly post about my child on Facebook. This must mean she intends to be in my child's life? What, if anything, can I do about this? How would you ladies feel? x

Edit: The relationship can't be that serious as they've only been dating since about June. He's had a few relationships in the past none of them seem to last