He has a psychiatrist who has provided the medication but is he doing ANYTHING besides taking medication (that isn't working)? Does he spend time with the psychiatrist in counselling or just updates on medication? Is he doing any of the things that people with depression are told to do - sleep, exercise, eat healthily etc? Is he getting regular reviews of his medication because a year seems a LONG time to be on something that isn't working. You've already said he's not having any other therapy.
I am not saying you're being abused. But I am saying that if he refuses to seek help for his health problems and as a result you and your DC suffer, then yes, that's abusive behaviour.
The guy is ill & some people think his wife should just walk away?
No, people are saying that if he is not willing to do anything to help himself get better, then she should consider walking away. I was struggling - felt tired, down, irritable etc etc etc.... DH bore the brunt of it because I was miserable.
I called my GP. Did lots of tests. Discovered various deficiencies, most notably iron and vitamin D. Took the supplements. Made an effort with other things such as sleep, stress, health, diet. Felt better. I did all that for myself but ALSO for my family. Depression is much much harder and more complex, but that's not an excuse to simply opt out.