Why is my mom being 2 strict about everything please help?

when my mom was my age my aunt (very close) said my mom would always watch horror movies and do a lot of things I can’t do now like walk accross the street 2 walmart (I live in a small town not a huge city) my mom would walk everywhere when she was my age my friends asked if I wanted 2 walk 2 walmart with them before practices start for a play I’m in. She’s making me ask a teacher 2 take me… She doesn’t want me 2 get hit by a car. I’m 15 btw. And this really awesome movie came out called The Collector it looked and was really good my mom said I couldn’t watch it and I said when I turn 17 I’m gonna watch it she said she’ll burn it or throw it ou if I got it. I watched it online (the edited version) my mom grounded me for a month. It’s not fair she wouldn’t even let me be in the talent show why is my mom so strict she used 2 watch rated are movies all the time she walked everywhere she was always in the talent show she says its because we’re a christain family (which I’m a christain) its not good for me 2 watch rated are movies because all the images get in my head what do I do she won’t even let me get a job. I’m sick of it I’ve tried talking 2 her no luck please help

btw I even get grounded if I miss church she won’t let me get a boyfriend I even have a crush on a straight A student she still says no what do I do