I was very sad to hear your news, you must all be devastated. I am no being flippant but I would have thought the best thing you can do is find a new cocker as soon as you can, it will nver replace what you have lost but will help I am sure. Also, please do not blame yourself, dogs at any time can on that one occasion revert to their instinct and go off for no reason whatsoeover. Your experince reminds us all of this and we should all learn from it and take note. I hope that you will all be able to feel better and time being a great healer, I am sure you can. I hope you can find another Cocker that can help you find new happiness with a friend at your side. Thinking of you all at this sad time.