Are you wearing padded bike shorts? That might help. (Pearl Izumi makes them in XXL.)

I'm big, too, and it took me several tries to find a seat I like, but I settled (ha) on an Adamo Typhoon. It's cushioned just right and has a cutout in just the right spot. It works for me, anyway.

Good luck with your new bike! What kind of bike did you get?

Welcome to TE.

Roxy