Been there, it’s horrible. I’d asked my ex to wait until 8 months since we’d spilt to even consider a meeting, but he went against it, they met after only 4 months.
Things I’ve taken from the experience, you’re allowed to feel any emotions you want, it’s normal, but don’t show your child, better to say nothing than to make them feel bad about seeing them. You will ALWAYS be mother, and the new women can’t take that away, you bond won’t allow.
I hope it works out ok