Hi, I hate Sundays. I've never been fond of them. I still struggle feeling down on them. You are not alone. Google it and read up on it. I no longer spend my day drinking. I do make sure I have a routine set up. I attend church in the morning. While church may not be your bag, substitute something else and do it every week at the same time. Could be working out. Going to have coffee and read the paper. Then I try to make plans that get me out of the house. Visiting relatives. Going to a museum. It varies.
The fact that you know that you don't like Sundays is half the battle. I always used to feel sad and empty on Sundays. It's gotten much better since I quit drinking. I think maybe part of it is unmet expectations. What I didn't get done on the weekend and the upcoming week.
Check out the weekenders thread. It helps me. It goes up on Thursday morning.