Intro (end of the world). How can I tell if I'm in the right relationship

Intro (end of the world). How can I tell if I'm in the right relationship? Aren't you really supposed to know that thing? Feel it in your bones and own that thing? I don't know. Then I had this interaction, I've been thinking 'bout for like five weeks. Wonder if he's thinking 'bout it too and smiling, Wonder if he knows that that's been what's inspiring me, Wonder if he's judging me like I am right now... I don't care. I'd rather tell the truth, Than make it worse for you. If the sun refused to shine... Baby, would I still be your lover? Would you want me there, If the moon went dark tonight? And if it all ended tomorrow, Would I be the one on your mind? And if it all ended tomorrow, Would you be the one on mine?