A great burden was lifted from my shoulders the day I realized that no one owes me anything.
Everyone will experience the consequences of his own acts. If his acts are right, he'll get good consequences; if they're not, he'll suffer for it.
Everything you want in life has a price connected to it. There's a price to pay if you want to make things better, a price to pay just for leaving things as they are, a price for everything.
You don't need an explanation for everything, Recognize that there are such things as miracles - events for which there are no ready explanations. Later knowledge may explain those events quite easily.
