How do I cope with feelings of guilt brought on by moving away from my mother?

In 2006 I moved to Florida with my husband from Pennsylvania. I did so because my husband really wanted to live there after retirement. My mother was furious and says that I abandoned her. My father passed away in 1998. I have two brothers who live in the same town as she does. Whenever I visit or talk to her on the phone, she constantly brings up my abandonement, how lonely she is and how she will never forgive my husband for taking me away. It is getting to the point where I do not want to call her or go up to visit. As it is, we get up at least 4 times a year (more before the economy crash) and we fly her down at least once a year, sometimes twice. I am feeling mentally battered by her, yet I don't want to say anything because of her age and I don't want to upset her with a confrontation. But it is really eating me up inside. Any advice? Am I being selfish? I feel torn between her and my husband.