"Usually I’d brush this kind of thing under the carpet for a peaceful life but this one is too much and I don’t think I can"
Hold that thought, because you really must not brush this under the carpet, and you must not let him backtrack and downplay it either.
"Usually". So - he has form, if you can invoke the word 'usually' about this scenario. He's done this, or shit like this, often enough that you have a 'usual' response. There's a phrase I first read on here, which goes "If you do what you've always done, you'll get what you've always got" - and that's where you are now. So, do you do what you've always done ("brush this kind of thing under the carpet for a peaceful life") and get what you've always got (an un-peaceful life as he feels empowered to pull this shit on you again), or - do you take the bull by the horns and say 'NO MORE'?
Would I be right in thinking that he is escalating his behaviour? It's implied by "but this one is too much", but it would also be in keeping with how abusive behaviour works - start small, push it gradually until total control over the abused person is gained. Sometimes referred to as 'boiling a frog' (put a frog in boiling water it will instantly jump out, put it in cold and gradually heat and it won't - even as it dies
.
This time, he has pushed it to the max. Not just the locking you out, not just the accusations - what he has done that makes this dangerous to you is that HE HAS DONE IT IN PUBLIC. He's not just boiling you, he's boiling all your friends. All of those at the party will be aware at some level, and what he is trying to do is to isolate you from them, because by and large 'don't get involved!' instinctively kicks in with a lot of people. Which means there might be nobody in your circle of joint friends who will take your part next time he kicks off - which will undoubtedly be a further escalation. This incident will have left them feeling uncomfortable, and uncomfortable people tend to look away.
It's shit, but it still happens.
SO don't let him boil you into that scenario. Put a stop to it NOW. Say 'NO MORE' and mean it.