Well, fortunately, that's over now. The same exact thing happened to me; I got too emotionally invested and it couldn't continue in any realistic way. Either way, I've learned a lot from it and hopefully I won't make the same mistake again.
6 years? That's amazing. I've never been able to keep a single pair of glasses for long because my eyesight keeps getting slightly worse each year. It's kind of concerning. Also, where are you managing this growing group of people?