Cheating and Ghosting

So I was meant to be bringing my boyfriend of a year to my family’s for an event. About a week before this, he starts not replying very often. He went three days without a replying so I sent another message checking in with him and he messaged saying he had been working loads and everything was good, replied to this asking about the family event and he hasn’t messaged me in about a week. We get to the day we were meant to be leaving and I hear nothing, try calling and no answer, end up making the decision to go on my own and having to explain to my parents why he wasn’t there. Cut to yesterday and he has read my messages and not replied and seen my Instagram story. I’ve had a feeling that he was cheating on me since he wouldn’t see me very often and would message once a day and now I think it’s definite.

I feel so broken and used. But I’m at this event and I’m struggling to be happy around everyone and having to tell people why I’m on my own when they ask. I just feel like such an idiot, I don’t know what to do.