u/MakingBlunders

I am in my 70s living alone as wife passed away couple of years ago. My routine is all messed up. I am retired. I have been eating dinner earlier and earlier. As early as 1230pm to 100 pm falling asleep 500pm even 430pm once. Waking up around midnight / Going for a 3-mile walk. I want somehow to try to stay up later, wake up later. I still want to walk at least hour before sunrise as its cooler and out of the sun. I live in Hawaii. Anybody have any suggestions? Thanks