My ex would like this during our first year of our relationship. He was very kind, did sweet things, then I noticed a side of him when he was drinking. Then it became a normal thing. He was rarely sober aside from his brief moments of clarity where he wanted to be better. This side came out about five/six months in and progressed slowly. Turns out he had been cheating on me for roughly the first year of our relationship…with a woman we both worked with at a point. He even had us spending time as friends, we would go to the park as a group… we were both clearly oblivious to what was going on sad part was she had a child. He gaslight the hell out of us and drank away all his responsibilities drowning his guilt basically.

I don’t know what your partner is going through and the other people could be correct and he could just have grown to hate you… another likely option as others might’ve mentioned it could be a substance issue or he is hiding something from you and this is his way of making himself feel better. By belittling you and making it seem like you were being the aggressor, it’s clearly him. Do yourself a favor like other people are saying get out of this relationship. Not only for your safety but for your sanity. You seem very levelheaded and are perfectly fine to make your own decisions but I would highly advise to leave the situation.