Charles seems to have always preferred a batchelor lifestyle, or at least one where he sets his own schedule. In the early years of their marriage Diana was often left at KP alone while Charles disappeared off to Highgrove for days, if not weeks at a time. He described their uninspiring “Honeymoon” on the Royal Yacht Britannia in his diary, where Diana would go off to talk to the naval shipman and the cooks as he preferred to sit and read through his many books by Laurens van der Post. He thought it was idyllic, poor Diana!
Then they went up to Balmoral for a month or more with the RF and a crowd of the Prince’s friends. He would go off deer stalking from 9-5 while leaving Diana lonely and bored in the castle. I just don’t think he has ever had to really change his ways for anyone. Camilla was very wise to keep her own place, she knows how he likes to live.