Why is my boyfriend such an asshole?

Seriously why? It’s like he loves to piss me off and get mad for no reason. Playing mind games... ignoring calls, making me chase him, getting jealous all the time... and blames his ex cheating for making him this way? HIS EX FROM 10 YEARS AGO. He calls me names and says things he knows makes me upset. Things from my past that were traumatic. I have tried helping him but I am so tired.
Why is my boyfriend such an asshole?
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