So sorry for your loss. As hard as it is to do get another dog as soon as you can. You almost feel guilty at first replacing you lost loved one but your best friend would want the best for you and that is to be happy not sad.
My wife and I couldn't have children so our pets are very special to us. We had to put down our female Chesapeake Bay Retreiver about seven years ago due to cancer and it tore my wife up. She was closest to her. It wasn't too long before we got another chessie named Ellie and she is my girl this time and even the thot of losing her one day tears me up.
My wife's cousin, with whom she was very close, passed away suddenly last year about this time and he had two male chessies, Colby and Saber, from the same breeder as ours. We took the two dogs as our own. Early Fall we had to put Saber,the older one, down. I think he missed his master so much he just didn't want to live anymore without him. My wife laid on the vet's floor with him as he got his needle, loving him as if she had him his entire life.
We had talked about getting another dog sometime so we would never be without one and we couldn't have gotten a better dog in Colby. He and our Ellie get along great.
There is a reading posted in our vet's office that says you think your heart is so full of love for your lost friend that you couldn't possibly love again then you see that puppy and you find there's room for one more.
God bless you and keep you until your next friend comes along.