Hold your head up because you have every right to. Tell yourself you are a great individual and believe in yourself, for if you don't believe in yourself, no one else will believe in you.
Everything happens for a reason. Nothing happens by chance or by means of good luck. Illness, Injury, love, lost moments of true greatness and sheer stupidity all occur to test the limits of your soul.
Without these small tests, life would be like a smoothly paved, straight, flat road to nowhere. Safe and comfortable but dull and utterly pointless. Complacency IS safe and comfortable, but doesn't thrill you. The people you meet affect your life. They have the power to change your entire way of looking at life. Never settle just because that's what's normal or expected of you. Keep shaking the tree and soon enough, a bounty of fruit will fall down from it, all in your arms.
The successes and downfalls that you experience can create who you are, and the bad experiences can be learned from. In fact, they are probably the most poignant and important ones.
If someone hurts you, betrays you or breaks your heart, forgive them because they have helped you learn about trust and the importance of being cautious to whom you open your heart to. If someone loves you, love them back, unconditionally, not only because they love you, but because they are teaching you to love and open your heart and eyes to little things.