This song is basically self descriptive.
But the whole idea is about loving someone and although you can be really upset about things you can't control, they make life better and that you feel happy about things even though still being sad.
Also missing someone even though you only saw them recently.
And there's a part saying never be undercover, it's where not many people know that you love this person and you're saying you know what dude, I think we should just act how we want to and let people know cause I love you and I know it.
HAPPY SONG :D Shocking.