Not sure

Ok so this weekend I was drunk and had sex with an ex! so my ex best friend dated him after I did and they are broken up and she currently has a new bf. So she found out about the whole sex situation and she's like telling people and I guess she hates me for multiple reasons! But the only reason I could understand if she hated me is that she still has feelings him but it's not like we're friends anymore so I just don't understand the situation and need some input!