"You can tell me anything and everything. Trust me." But when a break up happens, those things get used against you 🙄

I hate how this happens so often, I’m sorry you’re experiencing it too. Actually, it’s just those kind of people who should reflect on themselves. Trust is an essential ingredient in a relationship, don’t let other people (or an ex) ruin your future relationships with their issues ;) xx

I wouldn't do that at all, I never shared 'secrets' of other people, not even people who betrayed me. So I won't do it with things of a partner.
Anyway I'm a bit naive or too good-hearted about this...

Yep. Never tell anyone your all. Most things go haywire at some point and they will gladly tell their friends or whoever, all your dirt.

That is a sad commentary on love. I have only had one partner that I ever trusted with even my secrets. Love is about sharing everything. Why love if you cannot trust? That is what I believe. Welcome back.