First of all, hello. I am new to this section of the board as well. A little history. I have several medical issues and have been active in other parts of the healthboard. However, I am currently going thru a divorce and am a victim of emotional abuse.
Now, I know you didn't go into a lot of detail, but I felt the need to give you my answer to your question. Of course it is still abuse! My soon to be ex-husband has many mental issues and so does his mother (hereditary), and possibly my youngest son. But, that doesn't give them a license to emotionally abuse someone. Whether by example (nurture) or by heredity (nature), he was still abusing us. Mental illnesses like ADHD and OCD and the environment that they grew up in, do not take away choices.
However, I play a part in here as a victim. I have no fault in this, but I had a father with a bad temper, and I guess I allowed some of this to continue and escalate because I thought it was normal. (Very common in abused victims.) And, like you I gave excuses for the way I was treated because of his mental and medical issues. I thought that once they were treated, then he would go back to the man that I thought I married. Also, because of my religious beliefs against divorce, I stayed to try and save the marriage for me and the children. (Also common in abused victims.)
I didn't realize the role that I played in all this until I read a pamphlet in the police station on domestic abuse. I was turning in the guns my husband has to the police on a court order of the restraining order and while waiting I read the pamphlet. So many things lit that light bulb above my head like the controlling, withholding affection, isolation, destroying property, etc.. And, then I read the victim's typical behavior and there I was. I had been a victim of emotional abuse and didn't even recognize it until I saw it in black and white.
Read everything you can on abuse. Education empowers you. And, I'm not going to take the abuse anymore. My children and I don't deserve it. And neither do you.