Your story will be one about failure if you insist on defining it that way. Those words sound harsh, and they are. But the reality is that you are what you think you are. Are you a failure? Are you someone who's struggling through failure? Are you someone down on their luck?
Or did you decide to "flip the switch" and decide that the failures do not define you?
If you chose the latter, you made a good choice because the rest of your mind and body will follow. Our concious thoughts shape unconcious and subconcious states and behaviors. You know this. You can absolutely imagine things for yourself - both good and bad. They are as real as you want them to be. You give the meaning and power to those thoughts in a way that can make them into not just a reality, but a way of life.
For better or for worse - that pendulum swings in both directions. Negative thinking shapes negative outcomes and positive thinking shapes positive outcomes. But what if it's not just simply "negative versus positive" and instead, negative behind holding onto the past and positive looking towards the future?
I think that's a better way to frame our thinking and our actions. "Being positive" carries a good bit of baggage. It feels like a chore and an obligation. But instead of saddling yourself with that, why not instead think about working towards the future? What is it that you want to be? It's time to be it - and the rest will follow.