experiance makes us tough and make us more adaptable to the situations..we know the value of happiness only becoz we have tasted sorrow..its said you don't realise the value of your eyes until you lose your sight..well there is a reason for everything that happens in our life..even the slightest thing..you will realise when you track each and every incidents that happened before something bad happened to you..and I really do belive that we are the only one responsible for whatever happens to our life..so the bottom line..learn from the mistakes rather wasting time regretting.