I agree with Aly on this one. You did made a unselfish decision. Many years back my Mom had to move from her house to a assisted living apt. and her poodle who was 10 years old came to live with me and my husband. And her dog also had spent lots of time in the past at our house and got along great with our dog (lab/greyhound). Of course she really missed her baby but felt that she was being taken care of and had a fenced yard to play in. When my mom would come to visit the dog would get so excited! Of course she always brought toys/treats. I think the dog understood that she couldn't live with her but she still loved her and hadn't left her for good. Sorry I got carried away with my own story.
Welcome back Snowy's mom!