In my opinion a promise is a promise. I do get a bit annoyed when I read about the amount that people cheat and think that the term 'til death do us part' should be rephrased as 'lets stay together until I find someone cuter/fitter/more compatible.'
I have never been married but would love to be. I just know that I would have to be 100% sure about the person to make such a big promise. I know that people change all the time so I think that the marriage vows should be rephrased for modern times. It's quite sad though isn't it? I am very glad that most women don't say 'love, honour and obey' though!