Tyson, I'm sorry you are going through this.
I honestly think taking a year off is an excellent idea. I took a year off after high school to work and get some money and perspective. I'm really glad I did. Maybe you could get some kind of internship with a clinic or hospital where you can really evaluate if being a doctor is what you want to do. Well, not only what you want to do but to figure out if you CAN do it.
There are many valuable professions within medicine that don't involve the grueling schooling and professional life that doctors have. I'm not saying you couldn't be a doctor but frankly I'm more concerned about you living to do anything right now. Like I said before, probably a few times, your brain and heart don't care what is spiking your BP or pulse. They will haul off and give you a stroke or heart attack anyway.
You absolutely need to contact your doctors, especially your neurologist. At the very least, they need to check both your liver and kidneys to make sure that the drugs you are on aren't wrecking your organs or there isn't a buildup of drugs in your body. A comprehensive metabolic panel is always a good test for someone with MG.
I do understand the anger and frustration over not having a normal life. There are days when it completely overwhelms me. I HATE not being able to work and do what I want to do. Some days I can't even do what I need to do. It's not fair, for you either. I'm willing to bet, however, that you can find a way to a life that works for you. It may not be your ideal but maybe a compromise is a good thing.
I don't have any answers for you. I hope you can figure out what is best for you to do. Whatever you do, do NOT beat up on yourself. You are not a failure if you don't follow the path you want to follow right now. In fact, you are successful for admitting to yourself that it's not working and that you need help.

Annie
BTW, Screw everyone else. It ultimately only matters what YOU think of yourself.