ADHD is about concentration, focus, and distractibility. It’s not about being mean to someone you love. It’s not usually wise to try to diagnose oneself. We can’t see what others see. Your boyfriend would probably benefit from having an evaluation by another doctor who is not in any kind of professional or personal relationship with him.
That being said, your problem is not your boyfirend. Your problem is that your emotional state depends on your boyfriend’s mood. I urge you to take a look at why you let yourself be a punching bag. Why do you let his comments lower your self-esteem? Clearly he isn’t very smart about himself. Why do you think he is smart about you? Surely 3 years of mistreatement is enough to convince you that he isn’t going to change and that you can only expect more of the same if you stay with him.
At 35, you need to be thinking about whether you want marriage and a family. Please think hard about whether this man offers you the kind of future you want for yourself. Is he a good role model for children you might have? Is your relationship something you want children to copy in their treatment of you, of each other, and of their own partners someday?
If you can’t either change the dynamics in your relationship or extricate yourself, I hope you will seek out a counselor to give you emotional support and to help you confront whatever it is that makes you accept unacceptable behavior. You deserve better.
I wish you well.