Please reassure me that I can't wait for her anymore

I've been struggling so much because of the way we broke up. It's been just barely over a month but there has been essentially no communication between us directly.

I found out ~2 weeks ago from her best friend who "felt sorry for me" and told me (with proof of my ex saying it happened multiple times in a screenshot) that she has been casually sleeping around with at minimum 1-2 strangers she met at a party within a week of the breakup.

Our last communication was full of the stereotypical "you were so amazing to me but I can't give you what you want" and "you deserve better" and "you are one of the most important people in my life" to let me down softly and then she told me that I shouldn't wait but maybe after some time she could earn my trust again and we could get back together.

She now knows that I know she's been sleeping around and not going to therapy or putting in any effort to improve herself as she promised me she would and it has been a little over a week and she has not tried to reach out or explain herself to me at all and essentially has the viewpoint of "well he knows now so whatever"

Please just reassure me that she's truly not worth waiting for. I gave her so much in the over 4 years we were together and she left as we were in the middle of planning our engagement and months before we were going to look into getting a big apartment together. And now seeing her go from a woman who was so neglectful to me sexually and emotionally and lying to me saying sex was something she didnt want or need in a relstionship to be happy to someone who will give up sex to strangers is so disgusting. So please as an anxious style man reassure me that she's not worth waiting for and that she was right when she told me i deserve someone better than her.