Never, never, never, never give up.
No winter lasts forever; no spring skips its turn.
Obstacles are those frightful things you see when you take your eyes off your goal.
Leonardo Da Vinci
Obstacles cannot crush me. Every obstacle yields to stern resolve. He who is fixed to a star does not change his mind.
Obstacles can't stop you. Problems can't stop you. Most of all other people can't stop you. Only you can stop you.
Obstacles don't have to stop you. If you run into a wall, don't turn around and give up. Figure out how to climb it, go through it, or work around it.
Orison Swett Marden
Obstacles will look large or small to you according to whether you are large or small.
One who gains strength by overcoming obstacles possesses the only strength which can overcome adversity.
Henry Ward Beecher
One's best success comes after their greatest disappointments.
Others can stop you temporarily - you are the only one who can do it permanently.