Shake it off Paul! The fact that you hate it happened and the fact that you are thinking about what you can do to prevent it in the future shows that you are an ethical hunter. My first two years of hunting with a longbow I was 100% recovering deer that I shot. I had 1 clean miss during that time. The 3rd year, I lost 3 deer in one week. One jumped just as I released, one was hit well and I still can't believe I lost her, and one was just a downright horrible botched shot. All three were 15 yards or less and like you, I felt horrible. My point is, sometimes despite all the preparation and ethics in taking the right shot, things don't go the way we plan. I suspect sometime in the future, you will experience this again. I don't know what distance your shot was, but before you are to limiting on yourself, keep in mind that the odds of recovering EVERY deer you shoot will probably fall short of 100%. Only you can say whether it was a shot you should or should not have taken. The fact you lost the deer has absolutely zero to do with the answer. We should probably be just as mad at ourselves when we make a clean miss, but it does'nt work that way. For some reason, we shake those off a lot quicker.