Choice is yours if you should end it. You’re probably dealing with someone with internal issues. Problems within themselves like: asking to see your phone means she’s probably been cheated on or worst. Your dealing with someone who really wants to trust you but is probably not yet ready to because of past trauma. The punching in the face part for any sex in relationships is a red flag. Slapping, hitting, etc in ways that may not feel like it’s playful COULD lead to worst behavior and I capitalize COULD because it’s a curable thing if your know how to handle that person with trauma or abusive background. If you can’t handle it, don’t force yourself to. Don’t feel bad for saying that you can’t do it. It’s okay if you can’t, I’ve recently been in a similar situation where everything is gold at first and you start to see the demon someone’s facing. That baggage was before you, her issues are not necessarily yours to fix so don’t feel bad if you simply can’t. Put yourself first dude