So sorry to hear this and I can feel your pain,but you did the right thing. I would never let my dog suffer only to have her another month or so.It will be tough for a while,as they are definately a family member. I have my Mercedes photo in my profile and I look at her every day and think of the good times and the great life I gave her,and I am sure you will do the same.Maybe she and Sammy will hook up and play.
Just a quick story. When I got back from the vets without her,her best friend knew something was wrong. Avis and Mercedes were great pals,and I liked Avis,but she was not my favorite.For reasons unknown,Avis immediately hooked up with me.She was hurting and she knew I was too. From that day,she has never left my side.In a way she did take Mercedes place,not the same of course but she did fill a gap and made things easier. Being #2,I guess Avis did try harder.
Hang in there my friend and God bless.