Pakistan is like an examination hall . It does not matter you perform well or not but certainly you got more experience and more patience. In long term, these all positive and negative experiences would turn to positive.. :)
There are multi stories behind it . Some evil king named Hiranyakashipu. Holika was his sister her burning is celebrated as Holi. According to some accounts, Holika begged to his Prahlad(Son of Hiranyakashipu) for forgiveness before her demise, and he decreed that she would be remembered every year at Holi.