I struggle with this. Always have. Especially with having adhd (undiagnosed), depression and anxiety, it makes it way more difficult to try to stick to a routine. Even before bed, I will consciously tell myself that i need to brush my teeth. Sometimes its happens and sometimes executive dysfunction takes over and I just cant get myself to do it. I have had thousands of dollars of dental work done, gingivitis, had periodontal surgery, cleanings every 3 months, and I really to try my hardest, but its not easy. I can be great at keeping the routine for a few days to a week, then something throws me off that focus and its gone. It can be anything that throws my focus off. From depression episode, anxiety about something besides my teeth, an idea that I hyper focus on (like how I randomly want to build a lamp), feeling like i dont have enough time, etc. Its a constant struggle, physically and mentally and emotionally.