Am I overreacting

My partner (32M) and I (32F) have been together for 3 1/2 years. We live together with our dog and we’re talking about marriage - overall things are good. When my partner and I first started dating he would go out partying a lot and this would cause us to fight but over the years this has reduced a lot and he’s much better at communicating with me if he’s out. Fast forward to now - we went out for dinner last night with friends, after that finished he said he was going to go for a few drinks with some of the friends. I said no problem but remember we have brunch tomorrow for one of my family members. That he has committed to. He said it was fine just a couple of drinks. But next thing it’s 2am, not home. 3am not home. When I text him asking what’s going on he just says he told me he was going out and that he might have to skip brunch and he would be fine if the situation was reversed. I was texting saying that this hurts me and it embarrasses me in front of my family and I’m sick of him doing shit like this. He doesn’t answer any of my calls and eventually he either blocked me or his phone died. I feel so upset and frustrated that as soon as he goes out drinking any commitments we had no longer matter. We have had this conversation so many times in the past and I really thought we had worked through it. Am I overreacting? Do I just let it slide? Do we have some time apart? I know he will come home at some point and not want to talk about it because he’s too hungover and just wants to sleep. I feel like I can’t talk to any of my family or friends about this because the relationship is otherwise perfect. Help 😭

TLDR: my partner reverts back to old ways of staying out all night partying and cancelling family plans - how do I deal with this