We are where we are, because of our thoughts in the past. Thoughts become things. We consciously or subconsciously always think about something. The problem is that we usually think more about things we dont want, than about the things we want. It doesnt matter if we want or dont want something, well get what we mostly think about.
Try to observe your thoughts for a day or two. Do you mostly think about the things that you worry about, you dont want them to happen, you are afraid of, or do you mostly think about pleasant and wonderful things?
Your present situation is the result of your predominant state of mind in the past. And you are creating your future now. Your future will be like your predominant state of mind now.
The past is gone. You cant change it, but if you are dwelling on unhappy past now, you arent feeling happy now, and you are creating unhappy future.
Because youre creating the future now, only the present is important. By having predominantly happy and positive state of mind now, youre creating your happy and positive future. Its called the Law of Attraction. You can attract whatever you want in your life: happiness, wealth, perfect...