Sorry to hear about your loss. Definitely a beautiful dog. I've lost a couple dogs through my life as well.. definitely rough times. I feel for you. Just know that 16yrs is most definitely a dog who has lived a good life and that she must have had a good friend who took care of her to have lived that long. There was nothing you could have done to prevent what happened and while I know you wished you could have spent that last night with her... just remember the 16 years that you were able to spend with her. You made the right decision no question, don't beat yourself over it.