What I've learned in life so far, is that you can't cultivate confidence on old soil.
The soil and everything upon it has to be burned in a fiery fire before you can do anything with it, and only then, when you come from nothing, can you grow. Sometimes this is heartbreak, sometimes it's a death, sometimes it's complete desperation, but in every case it's something that throws you to the bottom of the pit and it keeps kicking you while you're down. Rock-bottom in every sense of the word.
Right now I'm there, but I only just stood up and I'm looking around me searching for the first stone I can hold on to, to start climbing.
But more than ever, does the fire burn in my veins now. I'm determined to succeed. Determined to arise anew.
If you don't have this, then you need to build momentum. Let every good choice contribute to the fact that you're moving forward. Use that momentum and become an unstoppable force. It doesn't matter whether it's deciding to go to the gym today or simply deciding to take a shower. Let every good choice motivate you to make another. Tip the boulder off the edge of the cliff and allow it to start rolling. Let momentum be the force that drives your will and confidence.
And stop whining and blaming things which are beyond your control.