I read somewhere that Susan Sarandon was married once before, but it ended in divorce, so she never remarried after that, on the grounds that she doesn't personally believe in marriage.
On another note, I remember she also mentioned once on a late night talk show that she was an unpopular girl in high school and she never knew why until she bumped into a guy she went to high school years later and asked him why, and as it turns out she wasn't sleeping around with the guys like the other girls were, to which she said, "I couldn't! I was Catholic!"