Welcome to PC.

I can't really say if you made a mistake or not. You will have to search your heart. I think it is important that any two people in a relationship have a safe place with someone very trust worthy to be able to dump on and vent to. I don't think that is trash talking but processing feelings in a healthy way. A way of letting go of them. This shouldn't be done in public or with someone he just met and of course he should stick up for you. We all need some place to vent without causing more harm. if he is still holding on to stuff and carrying resentments than maybe he is not processing those feelings in a healthy way. Is couples counseling an option? I kind of think all couples could use counseling because it teaches better communication, understanding, and processing of feelings and validation. You feel invalidated.