In addition to this, I agree that Chivalry forbade adultery and fornication which was teh basic tenet of Courtly Love.
In my world literature college course, we are learning medieval literature which a focus of Marie de France.
I have read two of her stories: Laustic and Lanaval. (I am sure I misspelled the first title)
Luastic had the courtly love theme as it talked about two knights, one was married, the other single. The single knight and the first knight's wife are in love with each other, but the husband gets suspicious. The wife uses the nightingale as a cover, the husband kills the bird and the wife is sad because she cannot relay her message to her lover via the nightingale. She sends the remains to her lover and the knight keeps it in a small golden casket and carries it with him everyday.
The moral of the story (to me) is simple: don't cheat, just don't!
But in relevance to courtly love, I see as the proper way to secretly cheat. It is only good in relationships, but it is a disastrous recipe for marriage!
On a note, the only "bridge" between Courtly Love and Chivalry would be the Virtue of Courtesy. But Courtesy in the Chivalric sense is a form of expression to show people that we have a good heart and good, authentic, genuine character. But Courtesy is not an absolute Virtue in Chivalry.
To recap and explain on what I see as the absolute Virtues of Chivalry (the traditional five) are Prowess, Courage, Honor, Faith and Generosity.
With this in mind, it is impossible to be involved in a extramarital affair, because being chivalrous sets us apart for the right lady love who would best embody the virtues of nobility, grace and honor.
This is my take on this subject.
(another side note is that I find Lanval to be a more interesting story than Laustic, there is honor within that story, probably one of Marie de France's best narrative poems.)
Enjoy!
At Your Service,
Sir Joshua Santana, Knight of The Lion Blade