When trying to learn a new skill - any new skill - it's easy to become unfocused, discouraged, or even to quit when you start to become frustrated. I remember constantly running into these walls of frustration when working on my metronome app (The Gnome). I was always determined to break through these barriers because I became addicted to victory. These victories over specific frustrations became addictive and inspired me to continue moving forward with the project.
The thing is, these moments of frustration (or perhaps we can call it friction) are simply indicators that you have pushed your knowledge and skills to the point of actual growth. Those are the crucial moments that will propel you forward if you stick with it long enough to break through to the other side. Don't be surprised when they come, either - true progress will always be accompanied by this feeling of friction. It's at that moment that you should be the most excited - consider it a tangible, visceral sign that you are within reach of a new level.
If a task or goal is overwhelming, break it down - simplify it as much as you possibly can. Boil it down to the simplest task or goal that still challenges you. Break through that barrier and you'll have something worth celebrating - a small but fundamental change in your abilities, and proof that you are making progress.