My mom wants to add me as a friend on facebook. What should I do?

[Andras]

It sounds like most of the feature and options in place won't be of much help to you (the facebook privacy groups and the fake accounts like you've made) if you don't want her to know that you aren't showing her the full story.

It's probably not the best answer to hear, but I think you're gonna need to bite the bullet and tell her, unless there are other issues that would cause that you haven't mentioned (i.e. you're in college and she's paying, you're living with her and she'd kick you out, etc.) I get the feeling she'll be unconvinced with a lot of how you try to hide it, and at some point it's gonna get out anyways.