They say that you never really know the lives you touch. I don't know who this "they" is. But they sure know a thing or two.
You just never know when a smile or a kind word will lift someone up. Perhaps out of a really bad day. Perhaps out of a really bad decade.
A simple, heartfelt have a nice day in the elevator ride up to your office can make humanity seem more human after a grueling commute.
A friend's statement that you deserve better can make you realize it as truth. Even when you know you do deserve better, sometimes it takes seeing it in writing, from a friend, before you'll let yourself believe yourself.
Another friend's asking are you single these days, because although they haven't seen you in a while, they knew, before you are even ready to contemplate, that this thing, whatever it is, is no longer making you happy.
A random cute guy at the bank smiling back at you.