Advice please

Hi ladies. I need some advice. Please be kind because I’m having a hard time right now.

I am 25 and I was with my ex for 5 years. I really thought that we would move in together and get married.

Well last year, he started acting different. Hanging out with different people. Drinking a lot more. We started arguing a lot.

He broke up with me a few months ago. He dated someone else but they didn’t last.

I am having a hard time with the break up. Cause I can’t believe he really left me. I truly believed we would stay together.

But now he’s so mean to me. I texted him and he told me that the other woman he dated was better than me. And that she was prettier than me. He said that I wronged him. How did I wrong him?!! When he was the one treating me badly.

I just can’t believe he turned out like this. Can anyone give me advice ??