Understood. It took me a long while to get over the death of the heart-of-my-heart Sheltie, Neechee. (He died the day after Easter 2010.) I cried non-stop for a week, and it was touch-and-go for the rest of the month. I couldn't look at a photo of him without tearing up, but felt compelled to look at his photo at least three times a day. Some really awful (yet religious) family members assured me that his spirit would not be waiting for me in Heaven, but was completely obliterated once he died. This was so mean and smug of them that I have cut off all communication with them.
Even now, when I have had Bela for six months, I still think of Neechee and cry. I can look at the photos now, but on occasion I still find myself missing him horribly and sometimes feel that there is a hole in my heart big enough to drive a Mac truck through. But Neechee was such a great Sheltie - such a wonderful ambassador to his breed, that I had to have another Sheltie in my life. Bela has filled the day-to-day sadness I felt, but I will always miss Neechee - he was my very heart. Bela is doing well despite her many problems. I love her very much and hope some day she may also be the heart-of-my-heart.
I guess what I'm trying to say here is that the grief is very sharp and hurtful to you now - the first year is the very hardest. But don't let that prevent you from getting another Sheltie. Somewhere, someday there is going to be a Sheltie who needs you, and you will need him. Don't miss the experience!
That kind of leaves me in a tough spot... I want to rescue, but I also really want another sheltie. 