I, too, missed this thread since I haven't been on regularly! I'm sorry for your loss, Marsha.
Yes, eye issues are sometimes hard to deal with.
Soon, I will probably also be making a similar decision for one of our driving mares. She is one of the full sisters I started with in 2010. Last year, she started developing serious Fibroids in her left eye (she was actually sold to me as already blind in her left eye - but we discovered that she wasn't). This year, they've "taken off" and now not only is her sight gone from the left eye, but the whole eyeball is "shrunken". I looked into removing the eye - as you did - and the cost would be reasonable with a younger horse that didn't also have issues with the right eye starting. I decided to let her be a horse instead, treating as needed when needed. Sometimes that means 2x daily washing/cleaning her face and eye and replacing of fly masks. Her right eye has now started developing fibroids as well - don't know if she will do well when completely blind. We may try - it will depend on her! We can bell both her full sister Bell and/or her current driving partner - so that she can move with them by hearing... She is still driving ok as a pair - but is reaching across to "touch" her partner more often then she used to. I haven't tried to drive her single since she went blind in her left eye. She does now get upset when she is "completely alone" - even when doing her hooves/grooming. She did much for my learning curve 4 yrs ago so, I am giving her leeway for her "condition" and behavior now. Otherwise, she's still a gem for us. She galloped up the pasture whinnying and bucking yesterday after feeding - made me happy to see.
HUGS your way and hope that you and Dapper Dan both get through your grief soon...