Secondly if you train regularly it will only be a week or two since you last had a fight. Training yourself to respond to threats is important and martial arts help to do that. You will find 'fight' becomes dominant over 'flight' response.
Thirdly martial arts training helps to build confidence. It is often this that is detected via body language by assailants that will avoid trouble. This is the foundation of 'fighting without fighting'.
Finally life or death combat situations are a state of mind. Are you prepared to gouge out another persons eyes or stamp on their throat to protect you and yours? Sorry to say that but you need to think about in what circumstances could you actually do this and having done it how you will live with yourself.
OP - take up something that you like the sound of and give it a go. Any skills you learn may prove useful and you will get a bit fit(ter) into the bargain
BD