Never be a prisoner of your past, for it was a lesson -- not a life sentence. There's nothing you can do to change what's already come to pass; all you can do is learn from it so that you don't make the same mistakes. There's no sense beating yourself up over past decisions that, in hindsight, you wish you hadn't made, whether that includes hooking up with your ex, taking a particular job, or making a poor investment. You should never lament anything that (1) once made you smile, even if it was at the very beginning (2) you ultimately learned from, making you a better person today. Our missteps, as a matter of fact, are our best teachers. It's through our mistakes that we gain the most wisdom. If we never made any, how could we ever better ourselves? Of course, that doesn't mean we should deliberately make foolish decisions for the sake of learning a lesson. But there's no question that all of us can cite at least a few choices we have made t...