Perhaps you could swap the uncomfortable one for a different shape? Perhaps where you purchased it they sell other seats? One shape does not fit all. Can this indoor trainer accept a regular bicycle seat? Or are you stuck with something from that manufacturer? I can certainly sympathize. On my 3rd ride on two of my bikes I was in so much pain I wasn't going to be able to ride anymore. I tried another seat and the godless pain went away immediately. I suggest to try another seat with a different shape.