I was wondering if it was a metaphor or something. But I think if you take it literally, it's about someone who's not committed to his current relationship. It sounds like he's emotionally leaving it and letting her know. If you tell someone you're falling in love with strangers every day, it means that you want to break up. Who would stay in that kind of relationship? "Falling in love with someone new; Love with every stranger." So he likes to fall in love with people he doesn't know. He's setting himself up for disappointment unless he's talking about one night stands. Maybe that's what it's about. I've met people who go through phases like that. Eventually, you miss a meaningful relationship beyond sex. It doesn't seem like he's emotionally ready for that.