Do your sit bones change as you get older? Or if you gain weight?

I've always ridden on a Fizik Vitesse and have never had problems and I ride them until I break them, basically. I put on on my newer bike and longer rides are uncomfortable! I don't know if it's me getting used to the bike again or if it's it. Or, I guess, that ever changing body chemistry.

I used to be able to ride in cheaper and less padded shorts and no chamois butter but things are changing I guess.

It kind of makes me laugh though because if I described the symptoms without saying what it was (burning when I urinate and itchy as it heals) it sounds quite a bit like a STD

I am looking seriously at those Brooks saddles. DH looked a bit exasperated and said "but you just got a saddle" which granted, I did, I just don't know why it isn't working!