* affairs are healthy

before bashing... just read a couple of lines (this is only a theory):

affairs (in married relationships) are healthy

his-story:

• marriage is difficult, as is cohabitation.
• marriage-sex (once you add kids, jobs, in-laws, religions, etc.) is (as a rule) not as hot as pre-marriage or honeymoon sex.
• married people do have affairs.
• the people aren't the problem.  conventional u.s.a. marriage (the construct) is the problem.
• making a lifelong promise (based upon emotion & subconscious sexual vibes) is a very, very bad idea.

but how could affairs be 'healthy'?  affairs (within a marriage) can be healthy if:

• partners use the "don't ask, don't tell" system.  there is no need to share information about who, what, when, where, how or how much. 
• limit the trysts to 1 per week (max).
• only have an affair if your sexual needs are not being met in the marriage, and if your partner is unable or unwilling to facilitate meeting those needs.

here's what will happen:

• each of you will explore what your sexual needs actually are.
• both of you will (most likely) stay in better shape.
• both of you will (most likely) treat each other better.
• it won't be a catastrophe, if there is lipstick-on-the-collar.
• you won't necessarily have to endure the process of divorce.