I've been mugged into my throat from point-blank (Euro 5 man 04, if anyone remembers seeing me with a bloody hicky there). I thought "****, I'm out" and walked off. If mugging, or the fear of it, is holding you back so much, maybe you need to pump yourself up with adrenaline more? By being mugged, 9 times out of 10 its because you werent aware of the situation and it will come as a shock. When it happens it happens, you cant control it...if you could control it then hopefully you shot the bugger that did it to you!
My 2p is spend more time working on how you can prevent it, rather than getting used to it. That way you might just stop it from happening in the first place!