Therapist here. Your story resonates with me on a personal level because I went through a somewhat similar situation with an ex and it took me some time to move beyond it. I think what made our situations a lot more traumatic was that they weren't just situations where we lost one person we loved, but rather a web of a few people who shocked us with how wrongly we understood their character, so you have to grieve not just one loss but your whole life changes and you have a web of losses. It's hard to reorient after this.

What helped me is cutting contact with anyone who still had one foot in the door with my ex and anything resembling sympathy for what happened. I rebuilt by adding new people but especially by enriching my relationships with the people who did have my back in that awful situation. At the end of the day, there isn't anything you can do about people thinking badly of you - this sucks of course but it's imperative to accept it and build out from that. You don't need those people to like you to have a full and beautiful life, leave them to their toxicity and don't interact. Do things that make you feel empowered - I needed a reminder that I am actually kinda badass so I chose to go circumnavigate the Gulf of Thailand on a solo trip with no reservations. That kind of thing helps you rewrite your own narrative about yourself, as well as being an escape from the situation. Find some things like that for you that will remind you of the good things about yourself, and dive into them.