I'm very glad you partner does support you, and sorry that you have so many problems meaning you do need that support so often. I hope your new meds and maybe resuming that therapy will ease matters for you.
It sounds pretty grim when you have to deal with anger, withdrawal and negativity from your partner, and I'm not surprised it is triggering at times.
I guess it might be easy to give a hasty judgment about his behavior however that is probably not going to be fair - or productive.
Many men do resort to anger when under pressure, either externally from circumstances or internally by depression or other issues. There is a pretty strong emphasis on masculinity in our society and in some ways anger can seem more acceptable than talking over emotions and feelings.
Then again, and here I'm not rying to be sexist, some men simply do not have the words to describe what is inside without assistance. I'm not a therapist, just someone who has gone down the same path in the past, and even now do not know all the factors involved.
I do suspect that often when one raises a subject it can be seen as a criticism, even when that is not the intention. Just asking how things are can be met with resentment. I know in my own case I was sort of pre-wired to see just abut everything as a criticism - it was very hard on my partner.
I would think the best sort of support you can give is to encourage your partner to have therapy or counseling to find the causes of his anger and depression. I know I did not improve, in fact got worse, until I had competent medical help.
If you find you are not able to persuade him there may be a friend of his or a family member who might be in a better position. What do you think?
Of course all this is no doubt putting more pressure on you, so may I ask what sort of supports do you have -is there anyone in your life you can talk frankly with? They do not have to fix things, just listen and care.
I hope you come back and say how you are going