I'm SO so sorry for your loss of Maggie
it seems to me that you did everything humanly possible but she was needed somewhere else (I know that doesn't help much but try to imagine her running free, happy & pain free with all the other Rainbow Bridge pets -and maybe one day you can really see her like that)
I feel so bad for you - I know your heart must be in a million pieces and even more if she is all you had.
Our lives can change in a split second and sometimes the hurt seems to be too much to bear.... but, if she had suffered more - you wouldn't have wanted that...
you didn't torture her so please don't feel that way and I can tell your Maggie knew she was very loved.
I'm very sorry.