My condolences go out to you, and commend you for being brave enough to watch your precious Rosey endure the excruciating pain. I'm sure Rosey a small semblance of comfort, knowing you were there with her until it was time to enjoy forever green pastures.
Did a web search on the diagnosis, and my heart goes out to you and the vet who did everything possible. Your Rosey was a very brave mare to have endured this condition, and the best way to honor her was "being there" until the end.
May God mend the hole in your heart where Rosey was held so dear.