Just stay positive. If that doesn't work, fake it. Most experiences are fleeting. As we move from to the next, remind yourself that life will not stay that way. It changes all the time, good things happen and bad things happen to every one of us, all the time. Keep perspective on life and these fleeting experiences will become easier to deal with, and you'll be able to better see what lessons are hidden within everything that happens and how we respond.
This pic is one of favorites of my incredible daughter Liberty. Sorry if it's sideways. I'm posting this from my phone, and odd things tend to happen when I do. It is what it is.