It is time for you to move out. Although you mom is doing what she thinks is best for you she is missing the biggest point, which is that you are happy, and she can’t find a way to be happy for you.
Get everything in place for your move. Know where you would go, when, and how the mechanics of it would happen. Have details and a real option ready. Then have a chat, just you and your mom, about how difficult it is for you to have to deal with what is happening and that you need to make a change. Explain that you are planning to move unless you and she can find a way to make it better. If she can respond with any openness then it is worth trying to have a talk or meet with a family therapist. If she can’t work with you, then you have your answer.
Wishing you patience and peace,
Proof Positive Blog @ PsychCentral