I have an alternate viewpoint here..

While yes her being abusive to you is a major issue, I have a bit of sympathy for her position. 1. You have identified yourself as having depression 2. You have indicated your calls are regular like clock work. I then kind of see how she would be worried when you didn't call during the regular time.

Still no excuse for beating you up for it.

I know my family members freak out with worry if I don't immediately respond to their calls and texts. I've pointed out that I have a life, that I could be indesposed when they called. Yet, they still get overly worried to the point their own anxiety is over the top.