I like this poem because the writer tell me many things about a hopeless romantic and falling love. There are so many different colors in fall, so that means the relationship had many different emotions.
You would never know someone you've never met, so this would translate to how writer feels it's impossible to ever forget him. I think we can all conclude that her regret was very strong and very saddening.
Everything was fast, wild, and great, until Taylor reached the end of the relationship; then she felt very emotional.