My bf is moving and I'm torn what to do?

I'm in a very long relationship with a partner I don't live together with. We love each other but we're not good with living together. He is annoyed with many things I do. It's not that I do wrong things, but he is just mad at me for silly reasons, like if I put a spoon the way he wouldn't do it, he gets mad. He criticizes me a lot for stupid things and starts arguments.

He is in a way more intelligent than me, but not emotionally I think. I ignore his tantrums but it's very hard for me being sensitive to be around such negative energy. So we live apart.

I tried talking to him about it because I hope we do live together one day, but years have gone by and there is no progress. He knows what he's doing and he always apologizes for it, but keeps doing it.

Now he's moving to another country for 6 months for a job. He asked me to go with him. I wanted to go, but I've changed my mind the last minute. We went on a vacation for a week recently and it was terrible. He was being mean to me a lot of times. I couldn't wait to get home away from him.
So that's why I decided not to go with him to another country.

He was surprised when I said no and thought it was for bunch of different reasons. He didn't know it was only because he was treating me badly.
Part of me wonders is that even possible that he is unaware? I wonder did he do it on purpose so that I don't go? I don't know. I'm tired of talking about same things so I let it go.

We've been apart like this for months years ago and stayed together. He missed me a lot and promised every thime he would never ever leave me like that again, but he did. And he will.

I don't wanna breakup with him. But I'm so sad he is leaving for so long. I doubt we'll grow apart or become distant. In a way we already are. But I'm sad I'll wait for him to come back and the cycle will just repeat. He'll be nice to me for a while and then mean again. I wouldn't say he is abusive, but his temperament is clashing with my. I love peace and harmony and he is ruining it.

I obviously can't change him. I don't even know what I'm asking you here. What do you think about all this? What should I do and so on?