I'm with you. I play hard (3 or 4 hours) once a week and at the end of that me fingertips are screaming. It seems to help to alternate tough and easy songs. (Somehow I think if I really know a song I am more relaxed and press less hard).
Here's my secret. SUPER GLUE! If you put a little on the tip of your fingers and rub it around quickly you will get a nice coating that doesn't interfere with playing. Has anyone else ever heard of this? Did I make it up?