If you find yourself in love with someone, and that someone does not love you... be gentle to yourself. there is nothing wrong with you, but love just did not choose to rest in that someone's heart...
If you find someone in love with you, and you cannot answer that love... feel honoured that love came by and called on your door... but gently refuse the feeling that you cannot return, as love did not choose to settle in your heart..
If you find yourself in love with someone and the love returned, it still can happen that love chooses to leave... do not try to reclaim it and do not assess any blame... let it go, despite the pain... there is a reason and meaning to this... you cannot choose love by yourself... LOVE CHOOSES YOU...
p/s : believe it or not, i have gone through all the three conditions above... and perhaps the 3rd one is the most painful.. kan Pakcik..?! but it's okay, because the decision has been achieved... be happy.. i know u will, because.... well, Allah the Al-Mighty know what is the best for us..