Cheer someone up by sending inspirational messages to them. Share them via Facebook, Whatsapp, Twitter etc.
Everything happens for a reason, and everything makes you lose or gain something. If you gain something, good for you. If you lose something, you still gain experience, learning and motivation to keep going on and achieve your goals. So life never makes you lose anything.
Never compare yourself to others, because you and them aren't writing the same exam. Always aim to be better than the person you were yesterday - you are your true competition.
If giving up was an option, do you think God would have meticulously created such a beautiful planet for us? Just keep going on, and the fruits of your hard work will show up very soon.
Don't be afraid of making mistakes. Years later, you'll be calling them 'experiences' instead of 'mistakes' and they will be the key points of your success story.