What is Iris by the Goo Dolls about?

The song "Iris" by The Goo Dolls is a song about longing and unrequited love. It is about a man named Vincent who is in love with a woman named Iris, but she is with someone else. The man tells her of his love for her and how he would give anything to show her what heaven can feel like. However, in the end, he can only watch her from afar and dream of what could be.