How do I approach my overbearing mom?

I love my mom so much, but she can be a bit much sometimes. I am 19 years old and in college. I also have a job that helps me pay for everything I need. I have my own life hours away from home, yet my mom isn’t letting me live it. She has a tracking app on my phone and she texts me constantly during class. If I don’t answer right away, she yells at me, despite being in class. I recently got a boyfriend and she flipped out. I didn’t tell her anything about him and she went straight to telling me about all the lifetime movies she watches where the boyfriend ruins the girl’s life. She said that I ruined her Easter because I told her and she doesn’t trust me anymore. I am a good student and I haven’t done anything to lose her trust. She has done so many insane stalkerish things that normal moms do not do. I need to tell her that I want to be an independent adult, but she isn’t letting me. How can I do that without hurting her feelings or having her yell at me?