Not only is it a cool saying but it's indicative of life - there are ups and downs and they kind of balance each other out. The caveat is that what you choose to focus on determines how you perceive the varied terrain of life. I started doing the 365 grateful photo project a couple weeks ago and feel like it is already changing my perspective. Living in America you would think it to be an easy task to find something to be grateful for every day but I've found it takes a unique attentiveness to find something to celebrate each day. Obviously this is partially due to not wanting to be redundant and repeat the same thing over and over but it shouldn't be very difficult to find a plenitude of things to be thankful for in each and every day.
Sure bad shit happens but that's why there are toilets - so you can flush it and move on. It's swings and roundabouts my friends and has been forever.