Cheating std

I’m 27 weeks and just found out my boyfriend cheated.. he won’t tell me who the girl is or anything about the situation. I’ve been having itchy bumps that appeared a few weeks back & didn’t think anything about it until i found this out.. anyways i went and everything looks fine with the bumps just waiting on the std tests to come back. But i was wondering if it was okay that i told her that he cheated? May sound silly but can i get my baby taken away because of this situation seeing as it’s stressful and maybe she’ll think i won’t be able to handle it when baby’s here? & any advice on what i should do when i get home? Should i even care who the girl is..? I want to know because i would like to ask her if it was more then once and if condoms were used, i just don’t believe anything he’s telling me i just feel so lost and heart broken. I don’t even know what to do from here ☹️