I have, unfortunately, had to fire on human beings in the course of my duty in Baghdad.....and I will tell you this, it will affect you for the rest of your life.
There is a very large "psycological hump" you have to cross overwhen faced with the prospect ofpotentially causing the death of another Human being.
If you have not considered the impact your actions will have not only on whomever you have been forced to defend yourself against; but on yourself, your family, and even those you associate with.....you need to put your firearms away.
Carrying a personal defense weapon is deadly serious, I do not say this to be obvious....or to be condescending, but all to often we think about the "what would I do if I had to pull the trigger" scenario, and the "I just now took a life in self defense" scenario.
I cant offer any suggestions.....each has to deal with that possible situation in their own way.