If it is truly your sitbones that are in pain, I have found 2 solutions. The first is ride more. OK, so you're doing that.
The 2nd is you may need a flatter saddle. The back of some saddles slope from the middle. Go to a shop where you can hold several in your hand up at eye-level and looking from the back. You'll see varying degrees of slope. That angle may be what is bothering you. Your sitbones need to be in the middle of the padded portion and bearing most of your weight straight down onto the saddle, not sliding off the sides.
Frends know gud humors when dey is hear it. ~ Da Crockydiles of ZZE.