The December issue had an interesting section on falling in love. My favorite article was actually “The Happy Couple” which explains how to stay in love.

In short focus on the positive. There is no worse destroyer of love than saying “That’s nice honey” to your partner’s excitement over something positive that happened to him or her.

The article is not available for free, but you can get a preview at:
http://www.scientificamerican.com/article.cfm?id=the-happy-couple