Honestly, I'm a bit more in between.
You just seem incompatible, that's all. He likes to talk about his relationship (he was part of the relationship so it was his to share in my opinion) and you don't. You're a much more private person.
Unless there was an intention on his part to bash you, humiliate you or berate you in front of his friends, I don't really see the problem.
My husband and I both talk to others about our relationship, even our sex life. The standard I hold myself to is that I wouldn't say anything to others that I wouldn't say if my husband was listening. I stand behind everything I say and wouldn't mind if these things were repeated to him.
But I do need to have other people's perspective sometimes, or to get things off my chest.
I will however always be respectful towards my partner. I will say for example:
"I can't believe he forgot to (insert chore he was supposed to do) again. It makes me feel so overwhelmed when I have to carry the household all by myself. How do I talk to him about this?"
I would never say:
"He's such a selfish ass for not remembering to do these chores. What an absolute wanker. I should dump his ass!"
Rather than convincing your ex of how aweful he is, maybe just focus on your future and look for a partner who shares your values and likes to keep relationship topics private.