Runaway

Question
We have a 13 yr old yellow lab and she loved to visit my in-laws house in the country. She NEVER wandered or strayed on us. On Friday she was fine and by two she was gone and there was no indication where she went. She was gone with no sign until today (Sunday) and we saw her trotting in the ditch. We got out and called her and she ran away from us. We followed her for miles calling and trying to get her to stop. She never did, and she got too far ahead of us. She would stop and look, but then just keep going. She has never done this. We are afraid we will never see her again. Have you ever heard of this before? Is this something that is common? We really don't know what to do. Thanks!

Answer
That does seem a little strange.  I have had some problems with my old lab wondering off and being confused, but she always seemed just as happy to find me as I was to find her.  

Just how good of a look at her did you get?  Is it possible you were really looking another Lab?  All I can suggest is to keep looking, put up fliers, and check animal control and vets' offices.