That's very sad to hear, MF. I can't count the number of horses that have passed through my ownership or care over the years. But somehow, in the back of my mind, they always remain "mine". And, strangely, I've never had to deal with hearing such sad news about any of "my" horses. But I still live through it vicariously with news such as this.
My deepest sympathy. ~FH
"Abuse is when a human action or reaction is obviously accompanied by anger, rage or adrenaline. Proper correction and reprimand are done in silence with thoughtful intent. Your horse knows the difference." ~FloridaHorseman