Why was she offended or disgusted? I don't understand.

Whatever your mother's reasons... you must look after yourself. If you need to cut off contact with her, do it. Forgive her, but don't let her wreck your mood or your life.

My mother was an abusive nightmare. I forgave her and am still in touch with her, but she is still very difficult. I cut her off for a few years but then let her back into my life. I often wonder if that was the right thing to do because she causes me some heartache.

Even if you stay in touch, don't let her take up too much real estate in your head. Assume that she will never change, and you'll likely be right.