I like what you said

difficult is way better than impossible.

That's all it is really. It's all about mindset and how hungry you are to achieve something. That's where discipline comes in, no matter how crappy you are feeling today, because you are hungry for success you will get up and go to work. There's a book by Brendon Burchard entitled High Performance Habits. This goes very well into detail and how to stay hungry.

Great post my friend, and thanks for the mention.