Doreen,
If she would not appreciate a call from you, don't bother yourself. If you think she might appreciate it, even if she can't express it, then you should consider calling. Calling your mother on mother's day is your gift to her. If she does not want it, don't waste it it on her. $0.02
I no longer have a mother to call. I wish I had been in a better position in the days when I could have called. I am sure she would have appreciated it, but I doubt she would have been able to express her appreciation. While I do not believe she was a terrible person, she had her own issues that helped to make our relationship dysfunctional. Oh, well. Nothing to be done about it now.
Stevi