Well, I have come up with two usable songs so far.
Mike Park: On That Stage
Karim once called this "THE Mike Park song." This isn't because its the best, or that his others are mediocre. They're all very good, but there is something about this one. You can really tell he loves this girl. He wants to grow old with her ("with every gray I'm more in love with you"). He loves that she loves him. They are best friends ("dear friend, the greatest friend, the thought of breathing here so close to you"). I really love this song because it remindes me of the period of my life when I had first fallen in love. I used to listen to it on repeat for hours. Beyond that, it has this purity that makes it really beautiful.
Bright Eyes: First Day of My Life
This one has wedding song written all over it. It's beautiful and the lyrics are perfect. The only problem with it is that it's about a couple getting back together after a breakup. It does, however, convey a perfect sense of love changing one's life, changing your perception of reality, etc.