Most marriages are rocked by infidelity as men often give in to their insatiable sexual appetite. Number one reason men look outside of their relationships for sex is because they're not getting enough of it at home. Other reasons for infidelity include a need for thrill or excitement, feeling bored by the sex they receive from their partner or feeling hesitant to share their intimate desires and fantasies with their spouse. According to "The Normal Bar," an extensive survey of 100,000 people published this year, 71 percent of unfaithful men and 49 percent of unfaithful women said sexual boredom was the reason they cheated in their relationships. Some say it's either entitlement/insecurity. Some feel owed, been there, some feel they will never get laid again, so they cash in.