I must be doing something wrong because I am looking at the Brooks website and can't find anything B68. Does anyone know how wide it is?
If your sit bones are 140mm wide, then the 155mm Riva was too wide for you. The B17 is 175mm wide; I know that for Brooks saddles you need to go a bit wider than with other saddles, but I would think that 175 would be wide enough. If you tried your husband's saddle on his bike, it's possible that it was too far back for you and you were not seated on it correctly. Or maybe I'm wrong -- there is a long thread on this forum about Brooks saddles, which discusses how to choose the right width among (many) other things.
Regarding Sky King's first recommendation, it is true that saddle position is as much art as science, and a small change to the position that your fitter recommended might actually be better for you.
I know what you mean about shorts -- I've been trying different brands recently and have had a hard time finding something that I really like. I had a problem with my LG Neo Power shorts similar to the chafing problem you're having, but it turned out that there was something wrong with the chamois which was allowing the fabric to bunch up and chafe. The WONDERFUL WONDERFUL people at TE have recently replaced those shorts for me under warranty. Of the other shorts I've tried, one pair had a perfectly-shaped chamois but it was too thick for me. The Gore shorts I tried have a very large padded area which I don't really like, though I know others who do find it comfortable. It's a very personal thing. My favorites have been the LG Neo Power Shorts (my first pair, not the ones that were just replaced) and my old Shebeest Century Elite shorts. I don't like the fabric of the new Shebeest Century shorts, but I think many people do like them and they are still using the same Century chamois, which I find extremely comfortable. Shebeest's Shelastic chamois is also very comfortable.
BTW I'm impressed that you've managed to ride such long distances with saddle discomfort.
- Gray 2010 carbon WSD road bike, Rivet Independence saddle
- Red hardtail 26" aluminum mountain bike, Bontrager Evoke WSD saddle
- Royal blue 2018 aluminum gravel bike, Rivet Pearl saddle
Gone but not forgotten:
- Silver 2003 aluminum road bike
- Two awesome worn out Juliana saddles