What is a woman's sole purpose for becoming a mother? my mom has always treated me like a puppet. she is never happy when others do for her.

Emancipate: You can't assume responsibility for another adult's happiness. Many people, even older folks, persist in behaviors that guarantee everyone will be unhappy. If your description is substantially accurate, pretending to love her doesn't work, and you are no longer dependent on her, go on with your life without her. If this is difficult, a short course of psychotherapy may help.