I had my mom do something similar with a slightly different reason/context/questions. I would end the phone call as soon as she started being inappropriate. She learned slowly that if she wanted to talk to me she needed to be appropriate. It was up to me to set the boundaries/limits with her and stick to them. Just because your mom asks you questions doesn't mean that you have to answer them. I found it much easier to do this over the phone. Pick a topic you don't want to talk about and end your calls with her when she brings it up. You have to be consistent with her in setting the limit. It is your life. They only have a right to the information about it that you want to share with them. Good luck.