The other day my wife and I were discussing the concepts of light and dark in relation to our behaviors. One common analogy that floats around is using paint. You start with white paint. If you were to intruduce black paint to it, there is no amount of white paint you could add that would make it purely white again. The contamination remains. There are a few ways to look at this concept. Some people use this to say why people can't move beyond who they are, they will always be stained by their past. My wife, however, uses it to say your past is always with you, as a lesson and a reference. (I'm paraphrasing). And that's certainly a more healthy way to look at it, because your past is not a hindrance nor an excuse. But I think there is another way to look at it, and that's using light rather than paint.
Personally I prefer the light analogy, otherwise I probably wouldn't have thought about it! So instead of viewing yourself as paint, think of yourself as a light with a dimmer switch. We start off in this life glowing brightly, full of love and life. As we grow up, we make choices that either reinforce our brightness or choices that turn our dimmer switch so we are less bright. These choices shouldn't be looked at as good or bad, but rather what is going to further us on our personal path through life, or restrict it. These choices are very individual and depend on the path that was drawn out before incarnating in this lifetime.
As time goes on, some of us make a lot of choices that send us in the exact opposite direction of where we want to go. This manifests in all sorts of life troubles, and eventually in our dimmer switch being turned all the way down, until you can only see the light if you look very closely at it. I'm going to claim that you can't turn it off, or you'd be dead. So at this point, if you've got yourself here, it would feel pretty darn dark, and you may forget that there is a flicker of light burning inside of you, just waiting to be turned on!
The thing is, that light is always there, and you can always decide to make better choices, which in turn slowly turn your switch up. The more you make choices that match your life path, the brighter your light becomes. With vigilance I believe you can turn that dimmer switch so that it is full on, just like when we came into this world. We may not stay there, because every moment we make new decisions. But our past decisions do not have to leave us sitting in the dark. As long as we make new decisions, the light will always and absolutely return. There is no tainting, no stains, every day is a fresh start if you choose to make it. And if not, then do it the next day! The only 'punishment' is that you'll sit in your darkness for another day.
This is the analogy I'm going to stick with for a while. I don't know if other's will like it. There are people who really prefer to view themselves as imperfect and unable of reaching happiness, joy, and love. But in time they will learn that those views are untrue. If not in this life, then when they return Home to whatever the afterlife is. (see here)
Some people may say this is a fluffy bunny outlook, but it is not. I am not advocating ignoring, hiding, or running from your past. I simply do not wish to see others imobilized by their pasts. You can choose to live the way you've lived your entire life, or you can choose to make new choices. They are not always easy. In fact, most of them are very hard to stick to. But we keep trying, and before too long real change comes. In the end the choice is up to you.