The idea that marriage is some sacred thing is outdated. The only reason we respect it so much is because we've been engrained to. Religions need a way to ensure that people stay with them, donate money, etc., and thus they say "no sex before marriage" and "marriage is the most important, make us more religious babies".
At the end of the day we are animals, we have urges, you're kidding yourself if you'll think you'll never want to have sex with anyone else ever again. And if you do, so what? It's so natural. As long as you're mature enough to know that sex doesn't equal love, then do you. I'm not saying you're bad to have a closed marriage but there is absolutely nothing wrong with an open one, and in fact it's just being more intelligent about love to know that there can be exceptions and that they don't equal the end of a marriage. Cheating is one thing, that's a lie and a betrayal. Openness is loving.
Hell no, my man is my man and I am his.
If there's anything sexually I can't give him I'll work for it until I can, not here for this 'seeing others' ********.
If we were raised in a society that was much more open sexually, that did not place such taboos on being sexual or equate sexual gratification with love, then we would look at closed marriages as being sexual prisons. Instead we see open marriages as being unsafe, overly promiscuous and unloving.