I broke my tailbone falling off a horse, and to the best of my knowlege there isn't a comfortable way to fix it. That was 30 years ago. I haven't ever had a problem with the tailbone in particular from biking, but sitting in other situations for long periods of time is uncomfortable.
I use a specialized Ariel which comes in different sizes. I'm 5'7", 160 lbs, and I have the middle size. Your bike store should have a gel thing they can have you sit on to measure your sit bones. Specialized seats come in different sizes.I really like mine so far. It has less padding than the other seat that came with the bike, and even when doing regular sitting I've found that less is better.