If you have an Android phone, get the Berto tire pressure app...

For 35mm tires, your weight roughly should be 81 rear and 66 front, the rims should handle that fine.

With wider and higher volume tires, you don't need to run 100psi in them, that's only for the skinny roadie tires.

I'm 260 and with 40mm tires I run 65 rear and 55 front and it is totally fine, I could really run less if I wanted to. The pressure drops with larger and higher volume tires.

Your 25 miles issue is just fitness, keep pedaling. I've been riding since the last week in July and can only get out once a week, 25-30 miles is my ceiling right now...only because I have limited time in the saddle.