I have had many medications, but the bad thing is that about medications take time to show effect and the best results are obtained by a mix of medications. So this process can take a long time. Also age is a factor and loneliness is one of the main causes and she should be involved in social activities. I’m not sure how old she is but there are groups that arrange social events for older people, and her attitude is the main factor. I had two grandmothers, both had arthritis, one also had a triple bypass heart problem. However she didn’t let any of that slow her down one bit, she would go golfing several times a week. Her hands would hurt at first but she didn’t let that get in her way. My other grandmother sat home feeling sorry for herself because her arthritis made life difficult. Get a good Dr, who is willing to work with a variety of medications. Many doctors, believe in handing out the same bottle of pills to every patient of their’s who have depression, and work on getting her out and about along with her attitude. But don’t put all of this on your back, you can’t help someone who doesn’t want to help themselves. She has the majority of the responsibility for her attitude, you have a life of your own, don’t forget about your mom, but live your own live, you owe it to yourself.