Dude, I've got 200% sympathy for the crap you're going through. It's great that you came here to vent about it because I think that getting rid of your stress by talking to people will definitely make things easier for you in the future.
Basically, if this is the way your mind is working if this is your speed bump, then we've got to create the mental detour that allows you to interact with a chick you like and even date and start a sexual relationship with her without triggering your epilepsy. It's not going to be easy, but if there's one thing I've learned about brains, people, and epilepsy, it's that there's a way. It's just not easy. Through brute force or finesse, you'll find your detour.
So maybe you'll have to trick yourself into this. Perhaps you could find a backdoor into dating this woman that you met - make arrangements to hang out with her that don't start off as a date but finish as a date. (eg. activity + dinner).
Another thing I'd say is don't build things up in your head too much. Shoot from the hip more often - rather than having conversations in your head and trains of thought that lead to anxiety, take action as soon as possible to deal with your thought. This way the thought can escape your mind and either lead to something positive or fizzle out as it leads nowhere (which means you're basically where you were 2 minutes before the thought).
You may feel like you're stuck between a rock and a hard place, but your anxieties can't be resolved if you don't act on your feelings. No matter what is going on with your epilepsy, you deserve to have a complete life where you can express yourself emotionally without fear of getting a seizure. There are over 22 epilepsy/anti-seizure medications out there, it may take you a few more medications to find the one that works for you but perhaps it's time for a change.
I'll give you an example from my experience just to show you that I've been through something similar. This was how I found my detour, so I know you can find your detour too. I've worked in a lot of jobs where I've had to train, explain, teach, demonstrate, or show information. That requires preparing speeches and being ready to answer questions. When my epilepsy was on the fritz, I would experience twitches in my left arm and a stutter while trying to explain things. So I basically couldn't do my job if my epilepsy was acting up. I tried to brute force my way through the problem, (you see, I'm quite stubborn: f$$$ epilepsy) so I'd continue to try explaining or demonstrating. The result would be that my arm would shake more violently and I'd temporarily lose my balance. If I really pushed things, I'd just fall down where I was standing. I was being dumb. But, I discovered that if I stopped trying to do my job for about 4-5 minutes and talked about anything else, then the problem would resolve itself and I could get back to work and I wouldn't experience another twitch.