Bad things happen to everyone and we all make mistakes. None of us are perfect. When you dwell on the bad things, it becomes a self fulfilling prophesy.
It's all about the power of your mind. If you think bad things always happen to you, your bad things radar will go up. In the process, you'll miss all the good things! if you think that GOOD things will happen to you, you'll recognize them when they do happen. I promise!!!!!! : )
But the important corollary question here is, "how do I stop sending the signals that it is O.K. for these things to happen to me?" Whenever I dare to go out and explore the world, there is always someone who moves in to take advantage--they are drawn to me like flies to garbage. What pheremone do I give off? I'd change my behavior in a New York minute if I knew how.
You might think this is crazy, but you almost always get what you expect, not what you want. A good book to read (less than 6 bucks on Amazon.com) is, "You Can Heal Your Life," by Louise Hay. That book has made my life so much better and easier.
Like bongus said bad things happens to all of us but some time we set our selves up for these thing or so I have been told. I think I do a lot of times.