Physical & Emotional Abuse Support Group
Abuse is a general term for the treatment of someone that causes some kind of harm (to the abused person, to the abusers themselves, or to someone else) that is unlawful or wrongful. No one deserves abuse, period. Abuse can be emotional, physical, or sexual.
Can you volunteer to do something at the church so you will be too busy to be in her company?
I am sorry you Mom wants to "insert" herself into it. I understand, my stbx has been doing the same thing, following me to the church where I have found so much healing, comfort and support this past year. But, fortunately, now it has mostly stopped since he sees it is truly over.
Don't stop going and being blessed because of your mom. You can't obviously tell her not to come, since it is a public place. But you don't have to sit with her either! If you have a friend or contact there already, make plans ahead of time to sit with them.
If your Mom comes and finds peace and healing, great. If she is just there to harass you and ruin it for you, don't let her. It won't last long if she sees you are not letting it bother you.