You ask for motivation? I give you the greatest motivation of all times that almost everyone fails to understand: DEATH!
Death, truly, is the ultimate motivator. Do this little exercise for me. Look up crime reports and news stories. Look up poverty issues and hunger struggles in third world nations where people are dying left and right, moment by moment. Look up support websites for the terminally ill patients. Go read their forums and some patient profiles. Go watch couple of good war movies and understand the character development of the soldiers and their ultimate, untimely death.
Do all of those things. What you will come to realize is that your existence, your health, and your life is temporary. You could wake up tomorrow with a terminally ill disease OR you couldn't wake up at all tomorrow. If this were to happen to you, then ask yourself these questions.
How will you feel when you're lying there at your deathbed KNOWING that you didn't live the life YOU'VE wanted? How will you come to a closure with yourself while the sword of regrets and missed opportunities dances above your head? How will you be able to utter these words that could not be farther from the truth, "My life has been a complete waste"? How will you be able to DEPART from this world when your physical, mental, and spiritual self is filled with anger, resentment, fear, regrets, mistakes, and failures?
Can you truly die a happy man?
Figure this you, and things will become a whole lot easier.