"Life is a sine curve... When you're in your highest moments, by definition, the down is coming. And when you're at the down point, by definition, the up is coming. the downs are connected to the ups and the ups are connected to the downs." [Jamie Metzl]
When you first read this, you might be left feeling a little depressed at the idea that when everything is swimming along smoothly, it's only a matter of time until it all goes pear-shaped. That is one way to look at it, or you can take solace in knowing that life is a series of "moments", so it's a waste of energy to get too attached to the good times and to the bad times. It's all about riding the waves and accepting that nothing lasts forever.