They all know her, she’s the centre of her friends groups.
It’s an age-old problem. Everyone seems to know her and everyone seems to know and probably dislike you because they know her.
Her being an ex-girlfriend and know she hates you and if she could she’d make a little voodoo doll of you and enjoy very much so stabbing the shit out of you.
There is no solution to this. If they know her and you think you like them well you’ve got to risk it. Maybe they won’t know about the little problems you told her abou. Maybe if they do they won’t bring it up. Maybe they’ll flat out reject you. Then it’s back to the drawing board.
It might be one big maybe but when should that stop anyone. A past indescretions shouldn’t stop you from being with a girl, I’ve learnt that in these recent times, and it’s a painful realisation to come to.