My dog is missing

I am so sad tonight, our doggy is gone! Her name is Abby and we've had her almost 6 1/2 years. We actually bought her when we were still in our apartment waiting to get into our new house (it always takes longer than expected to close on a house but being a first time owner we didn't know this). We had to hide her in the apartment for 2 weeks or so, and this wasn't so easy being a 8 month old German Shepard/Border Collie mix. Oops! She's been our baby when we couldn't have any, we love that dog so much. She is smart as can be and was always getting into trouble because no matter what we did she would get out of the fence... too smart for her own good. She was the mom of the house and took care of all of us. Unfortunately Friday or so she dissapeared, we're not sure where she is. Her buddy Rusty, our other dog, misses her terribly. He's hearbroken and it kills me. I hate not knowing where she went, if she's hurt or if she's dead even. I hope she's not scared wherever she is. We are going to head over to the pound tomorrow and check that she's not there (they told us they don't have her but I have to at least try). Had to share my sad story tonight, I never thought I'd be a dog person and here I am missing her badly. If she doesn't come home we're going to go find another one from the shelter for Rusty to have with him, he hates this so much.