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It's my experience that tedious people don't get less tedious.
Of course you're sad; that's what happens when you break up with someone. That you're sad doesn't mean that it was a mistake to break up with him. Why did you do it? Because tigers don't know if they like ice cream until they try every kind... because there's not a way to know if two people are compatible until they figure out that they aren't.
I'd be inclined to say you're doing the right thing in not getting back with your ex. The sort of person who puts other people down rarely changes. He may have decided for the moment that he was wrong to put you down for those traits in particular, but he'll come up with something new eventually.