I don't know what to do.

My name is Charlie. I’m currently 16. I have a girlfriend. I’m a girl that’s somewhat masc. I’d say I act like a gay boy. My girlfriend is 17 and is just a full on tomboy. We’ll call her “AL” for here. She’s got short hair, always wears baggy clothes, and could probably out-wrestle most of the guys in our school. She’s fiercely protective, sometimes a little *too* protective. She doesn't like my bisexuality, constantly questioning who I talk to, checking my phone, and getting jealous even when I'm just talking to a guy friend about a video game. The constant nagging and suspicion are wearing me down. I love her, but I’m starting to feel suffocated. Last week, she saw me talking to Mark, a friend from my art class. Nothing happened; we just chatted about a painting project. But AL flipped. She grabbed my arm, hard enough to leave a bruise. She called me names, accused me of flirting, and then…things got physical. She pinned me against the lockers. She kept repeating that I was hers, that I couldn't look at another guy. That I couldn’t *be* bisexual. It was terrifying. I tried to explain, to tell her I didn’t do anything wrong. I know I NEED to tell my parents but they’ll be even more upset that I’m with a girl than anything. And I just feel so stuck.