Looking back is a good thing as long as you don't find yourself getting stuck there. Be grateful for everything that has happened to you in your past, the good and the bad. You wouldn't be who your are today if they didn't happen. If you are unhappy with where you are today, well it is today and you can make a stand to make the rest of your life the best of your life.
Time to start contemplating, write a bucket list. Look at your life as tomorrow may never come and if you were to die today would you have any regrets? Is there anything you would think you would love to do. Perhaps places you'd like to visit, a job you wish you had, a business you wish you started, perhaps an idea you'd like to see come to life. Your goals are only limited by your imagination and the limits you put on yourself. Dream big and go for those dreams like you are dreaming and have nothing to lose. But do them while you are awake. Follow life as a child who is learning for the first time. Try new foods, talk to new people, meet people you always wanted to meet. Enjoy life like you won't get another.
Write those goals and start checking them off and when your time comes you will be full and happy and even leave a legacy behind. Live your lives and only look back to keep in check where you are going forward.