What am I doing?

Had a bit of a rough day mentally.  It has been a long week, I am pretty tired and I have been wondering why I am doing what I am doing.  I am having a challenge finding my motivation when I think about school taking an additional 4 years.  I am going to turn 43 before next semester so I am looking at being 47 when I finally finish. It seems to far away.  It is not easy to be back in school.  The work isn't always the hardest but it is finding time for school and life/familial responsibilities.  Today for instance, I came home from class and went to work on my online math class.  I stuck to it for 5 hours.  It was not something I had ever seen before and I did my best to learn it. I managed to certify and get through the lesson and am hoping I don't see many of these questions on future exams.  I'm fixin to pass out so I am going to call it a night.