A_DziekonskiI currently have salomon focus boots that have killed my heels.
The Salomon Focus is the same exact mold as the original SPK (without the stretch toe). This goes to show you how important the right boot is for your feet (as many have already said) and that you should also get supportive footbeds in addition to new ski boots. Footbeds do many helpful things for making the fit of the boot awesome, but in your instance they also provide more "cushioning" by placing your foot in its natural, strong state. Get the right boots (don't assume "park" boots will be the best option), get footbeds, and then if that doesn't perfectly work for you, have your boot-fitter add foam to certain parts of the liner to create more shock absorption.