I'm going to remove my mother off of my birth certificate and not tell her.
That feels very concerning. Why do you need to remove her from your birth certificate?
I heard that if I take her off the document she won't be able to get government benefits after I'm dead.
Any issues with your mom or anyone for that matter, it's best to talk with them and tell them what's bothering you. You wouldn't want people doing things against you nor making you feel left alone without them telling you why, right?
I'm going to remove her off the birth certificate.
If she had done something wrong, then the best thing to do is communicate with her to make sure she understands that you were hurt with what she did. Leaving her with no government benefits maybe harmful for her and she may find it very hard to cope with your loss just in case you died before her.