It doesn't take years to become adept enough to deal with the perpetrator of your experience. Wing chun will take six months, and many other street-proofing techniques, mostly simple but effective methods of convincing someone quickly that you are not an easy target, can take as little as three months. You do not have to be built like Schwarzenegger or particularly 'young'. (Wing chun was invented by a woman who weighted somewhere near eight stone, if that.)

Others may have better ideas. Good luck to you.