I just finished touring PCH from Canada to Los Angeles with my girlfriend and we unfortunately had plans immediately after our trip and had to be in LA on a certain day. So we took about 10 days when we reached San Francisco, but took zero rest days besides those. I usually go hard for a few days then take a rest day, so it was really hard to stay positive mentally and my body felt so exhausted after 30 days straight. I also feel like I want to go back to many of the places we passed through to take a few more days to see them thoroughly.
I would highly recommend scheduling a rest day every week even if you don't need it physically.