I'm glad Dumas is making a good recovery too! It seems like you handled it quite well. I don't think any one really wants
to think about the unexpected, but we do all have to. (i really have to start knowing about when to catch things and when to call the vet if we ever get a house to move the horses onto)
I think animals can rationalize what happened. I'm sure all what Dumas knew was that his tummy hurt him and then he got help from some very nice people.
My mom's dog, whom we rescued from a kill shelter, is just so loving and thankful for everything he has (he was abused and was found running loose by train tracks. His coat was all matted) But now he is just the happiest dog in the world.
This might have been what you and dumas needed to realize that he's a wonderful horse (not that you didn't know that already, but I know you were getting frustrated with him and had thoughts on selling him). I wish you, your family, Dumas and Twister the best!