I get pretty cynical about motivational quotes and posters and things, mostly because I don't think the person who expresses the sentiment has any idea of the context of it. For example, I recently saw someone use a quote from Victor Hugo's The Hunchback of Notre Dame about love. It was a nice little statement, but I doubt that the friend has any idea that (spoiler!) in the book, Quasimodo, the hunchback, dies (starvation), as does the love interest, Esmerelda (hanged), and the villain, Frollo (thrown from the top of the cathedral). It's a tragic story of unrequited love in the face of physical deformity, Church law, and different ethnicities. Using a quote from it for your marriage isn't bad, per se, but it seems somehow...unadvised?
Here, on the other hand is a good motivational poster that made me laugh, courtesy of S.T. Lewis: