[Lucifer666]

Normally when a woman look outside of her marriage for sex (mostly) mean there are some problems with the marriage.
The most common reasons in my humble opinion tend to be 1) husband having affairs 2) financial matters 3) lost emotional support and feeling for the husband due to some reasons.
I would said most women look for emotional support or relationships rather than sex. Unlike men, we look for sex and the best thing is to have many ladies to have to sex the better.