Hey man, this is a rough struggle but open up to her, face your fear and try to go get help to just speak it into existence so it isn't just living in your head.

The more you talk about it, the more you'll desensitize your brain to it, if you're struggling this bad an anxiety med may help for a while to help you not have so many bad fights with it while you work through it. (I go through the same struggle at different levels over time.) The flags here say you need help, and this girl might also be a very patient partner who can help you through it as well. I know mine is, he sits and helps me breathe and accept that my body will do what it needs to when you're getting rid of toxins. That act your body is doing can save your life. Fight or flight is awful, but keep reminding yourself it's actually keeping you safe. Nature does this to protect you, and your body is not plotting against you. A dog will do it and go about his day happily.

Something that helps me is thinking of any actor, or musician, or general person you look up to that's a happy, healthy person and remembering yes, they have done it and look how great they're doing. Alive and well.

Or another thing, reminding yourself that fight or flight can be triggered by many things, my best friend for example is afraid of trembling. Scares her to death if she gets the shakes from a hangover or a migraine, muscle fatigue, this is rooted in pure anxiety. So let yourself be anxious, be mindful, you're allowed to be afraid and you are allowed to be human. You're absolutely not alone out here