That is a recent thing -- at one time there was no bonus for combat pay. However the risk is your life not money and you can't deduct the loss of life on your taxes.
Plus just because you are not in combat does not mean your sacrifice is less great. I had an assignment where I would be gone 200 to 300 days a year. Now it was not in a combat zone, but I was never home. I was single so this was not a problem but some of the members of that squad had been divorced two or three times. No bonus for that.
So many issues with this response, but I'll just comment on one. You chose to be in the military knowing the requirements and many of those individuals who do end up getting divorced are usually at fault because they are marrying for the wrong reason; to get exactly what you are complaining about not receiving - those bonuses, perks and tax credits for being married and having kids! You mean they wont give an additional bonus for divorce.. those basta***!!
I am one who thinks active duty is a bigger sacrifice than to be just "away" from your ideal situation. I think most would agree..