How do you actually deal with it? Do you wait and keep on waiting in hope that it will bounce back up and return your investment or you sell and get whatever left of your investment?
Personally, I think that there is no easy way in dealing with loss. No matter how hard we tell ourselves that next time will be better, still we know that there is still a chance for it to not work out or to fail once again. So, the best thing to do is to forget. As much as possible try to forget the failure, but always keep in mind and never ever forget the mistakes and the lessons learned from that failure.