All the regrets, all the mistakes, all the problem's that you faced, are nothing hut learning experiences. The more of them you have the more to learn.
Even for me it's difficult sometimes I look back and feel good about things. However, to be successful I have no choice but to learn. It's almost impossible to be successful without failure because only then do you truly learn.
Start with the stories of successful people and the failures they went through. When others say they can't they went and did it anyways with full faith. Look at all the athletes that made it. Develop good habits each day with some fun as well.
Don't waste your time. Time is the most important asset in this life aside from people that love you.
Have a great 2019 and hopefully see you at the end of it with success.