My life has some parallels with the experiences you described. I got my teaching certification at 22 and taught for a number of years, then worked in a completely unrelated field for an equal number of years. When I accepted the realization that I needed to get back into the classroom, I took the coursework needed to get my certification reactivated (in my early 50's) and substituted until, based on relationships with a principal through subbing and community acquaintance, I was offered a fulltime position. During the years I was back in teaching, I obtained my Master of Arts in Education at age 56.
Finding a job is challenging, but I was very grateful to be returning to the classroom when I wasn't raising young children!