Hello, Sorry about your terrible beating. I guess I would be looking for a Self-defense course too? May I suggest a good book that may help with your future adventures in the real world and gives you confidence, the title is (The Gift of Fear by Gavin DE Becker) highly recommended for someone like you.
Next...One of my former Sensi always says...You want to learn to fight...take boxing? Want to learn Self-defense take Karate(meaning any of the Martial art out there) Boxing and Kick boxing teaches to fight from day one? and that is all you do is fight! The art of war: to win without fighting is the best way! This is what most of the martial arts classes teach. We say" we teach self-defence,but we mean self-development"! Just my thoughts and I agree with all of above feedbacks. Many choices, trust your instincts. ALOHA
Muay Thai and Mixed-Martial Arts are hardcore. They won't stop guns or knives, but if you stick with it and get good, you'll be able to beat the crap out of a lot of people.