You need to call child protective services and ask for help.

Regardless of what is or isn't wrong with your mom, it is WRONG WRONG WRONG of her to ABUSE her children in this manner with it!

And, yes, dear ... Intentional or not ... Whether she can help it or not ...

This is abuse and neither YOU nor YOUR BROTHER deserve to be manipulated or held hostage by it.

And, by all means, YES ... Get out as soon as you can ... Get the help you need to recover from this, and if your mom also gets help then perhaps somewhere down the line y'all can have a healthier relationship ... But as it stands now, this is not healthy for her, you or your brother!