I Need Help I Can'T Even Function

I caught my boyfriend sexting on Fb!! I have messed with a guy during a brake so I feel like he forgave me (even tho we were on a brake) so I should for give him. BUT he has been sexting her for 3 months she's from his home country so he says its nothing, she lives far away! He called her sweet names that'd he never called me we had a miscarriage it was bad I had to have surgery and I seen where he was sexting her while I was having surgery <3 I can't forgive this. am I over reacting??!