Need some support

My fiancé left me 3 days ago via text. No chance to work things out, nothing. He said he needed to "find himself" and work on his personal unhappiness. I returned his stuff yesterday and suggested that we backpedal; we didn't have to be engaged, we didn't have to feel so wrapped up in each other. We could focus on ourselves and still hang out and enjoy each other's company. He agreed. I found out later than night that he's already on dating apps, sending nudes, and making plans to hook up with people. I confronted him and he got angry and told me to move home. He told me that since I'd had a slutty phase when I was younger, it was his turn (he's 34 and his last relationship was 11 months) which I said wouldn't make him happier or help him find himself. I told him that I knew my faults in our relationship and was willing to improve them but he wasn't interested in listening or talking. He then tried to bully me into not talking about it by pretending there was a chance we'd get back together. He said "I feel that any chance we had is slipping away. And if you post any of what I did online, there's no chance at all. Not even to be friends." He left me so abruptly and now has cut me from his life. I'm floundering and I don't know what to do. Sorry for the rant.