I am so, so sorry. {{{{hug}}}}  The thing that helps me at times like that is to remember that animals don't fear death. They don't live their lives thinking of or worrying about it, and when it comes they aren't scared of it; they just go to sleep. You were there for her, and all she knew was happiness that you were there. All she knew in her life was happiness and being taken care of by you; she loved you and she knew you loved her. And right now she is in a sunny field somewhere, cantering through tall sweet hay, with no flies to bother her and no pain in her legs or body; she is young and strong, and one day she will find you there and the two of you will ride together again. I hope that helps. I wish there was more I could do or say. Just know that I and many others here are here, and are thinking of you, and sending virtual hugs.