You know those times when the whole world seems to come down on your head? Nothing in particular is going all that wrong, but nothing seems to be going right either. No relationships are right, no situation is good, no way seems any better than any other. All you want to do is pout and cry and sleep. Nothing makes you feel better, no amount of being told it'll be okay or remembering that at some point things usually round themselves out or praying for answers or comfort.
Then something little happens, and you can smile again. Like talking to someone you thought didn't even remember your name. And having them seriously want your advice on something, and a favor. Like they had actually thought of you before this chance meeting, and finally gotten a chance to ask what they had planned. The refreshing taste of unexpected care brings a smile and a laugh, carrying a little light into the dark room your day had been.
The people who knew you were down and tried their hardest don't mean any less because this random person happened to have the magic potion. To put in a cliche, "God works in mysterious ways." You place all your happiness on one thing, and that, for one reason or another, isn't helping you get out of your funk. Then Jesus winks and some random kid and a piece of pizza put your world back together again.