Why I will not treat family

Over the past 3 yrs I have heard from our Belmont Professors that it would not be a good thing to treat family members, for various reasons. I have agreed, and this is my reason for feeling this way.....
I have a horse..her name is Contigo's SuperLove, but I call her a Haven. I got that name from her mom's name, which was Pinehaven SuperLove, but I called her Ginger. Anyways....Haven has had continuing problems with her feet...for different reasons, but last week she started limping. This time she was actually limping on the tip of her left hoove.
So I proceed to put her in her stall and try to figure out why she is
limping. Although I am not a Veterinarian, I did get my undergrad degree in Animal Science. That combined with my PT degree gives me an in site into the foundations of musculoskeletal conditions...even in animals..we are all pretty much the same. I was working my magic and by Sat evening she was walking around better....well my dad thought we could let her out into the small pasture....I said, "that is not a good idea...she will start running around and jumping." My dad said, "she will not since her foot is hurting her." I said" Yes, she will b/c she will excited to be out of her stall." GUESS WHAT? He let her out...she walked out....then trotted...then broke out into a run...then began bucking and jumping.....Fast forward to Sunday morning...Haven is back in the stall....worse.....
It is now Wed....she is not any better..no matter what I do....
That my friends and family is why I prefer not to treat family..and some friends.......b/c they DO NOT LISTEN!!!!!