Are you seriously questioning your mom's instincts? Who understands women other than women themselves? If she said so far that your life would be living hell with her, Then sorry boy, BREAK UP WITH HER AS SOON AS POSSIBLE! Remember she's up to something. Are you rich? Maybe she's after money or some other resource. Never trust them. If you don't do it as your mom says, God help you.
Your mom saying "She's too much of a teen" and "Too high maintenance" - but I don't know what she's referring to.
If "too much of a teen" means she can be a tad unreasonable sometimes, She really likes going out, She's a bit of a risk taker - then that's perfectly fine. And if "too high maintenance" just means she likes asking your opinions a lot and she wants to spend time with you, Then that's fine too.
However, If "too much of a teen" means she's overly emotional, Immature, And is still trying to figure out who she is - you should be careful. And if "too high maintenance" means that she's overly clingy, And needs you to be there for her or else she can't take care of herself, That is very dangerous.
I don't know what is making your mother say these things, So I can't give any kind of accurate advice as to whether you should break up with her or not. You need to be more specific as to WHAT makes your mother say these things. What does your mom mean by "too high maintenance" and "too much of a teen"? We need those details to help you.
I got a girlfriend about 4 months ago and its been great my dad even said that she is the one and my mom said that she is a keeper after they met her for the first time. Which they have never said before. About 2 months in my mom started to say that I would be better off breaking it off with the girl. I asked why she said its because the girl is too picky with her food, Too high maintenance, Too many problems, Too much of a teen and that i would get tired of it too and it would make my life living hell. I am 21 and the girl is 20 the girl just got out of high school about year ago took long because of medical problems with seizures when young. I think the girl can grow up, I don't know if I want to wait it out to see what type women she will be. She says that she still likes the girl and she thinks the girl is one of the best that i brought home, But she just thinks she isn't the one now. Should I break up (yes) or stay with the girl (no).