why men cheat on their girlfriendsWhy do men cheat on their girlfriends?

Why do men cheat on their girlfriends?
and why do women have affairs with men that are in relationships?
insecurity, needs they want fulfilled, and love/lust.
help me please?

Because they are GREEDY..if you want to sleep with loads of people why get into a relationship in the first place. just DUMB.
I think its the thrill to see if they can not get caught or not.
The biological answer: Males are trying to ensure their patriarchy by having sex with as many females as possible (even if you look to lifetime mating pairings of some species of birds, you will find that the eggs of a particular female are not always from their life long mate (~11% if I remember correctly from a genetics study that was done)). By the way, most animal species (90%) are not monogamus and will mate with several partners over their life span:

http://en.wikipedia.org/wiki/Animal_sexual_behaviour

The social answer: Males in western society have been culturally habwhy men cheat on their girlfriendsituated to visualize sexuality in females and all their body parts: we are instantly attracted to your hair, smile, smell, curves, breasts, buttocks and any looks that you give our way is like a drug, a powerfull drug that makes us feeble are different for every cheater and every marriage. Here are the top 7 reasons given by cheaters to justify their betrayal:

1. "My needs are not being satisfied inside the relationship." He thinks that it's o.k. to satisfy his needs elsewhere. He is wrong of course.

2. "I never learned how to respect boundaries". He knows that they are out there, but he doesn't really honor boundaries and doesn't hesitate to "jump" over them.

3. "I have sexual fetishes that I can't share with my partner." Sometimes he can't share them, and sometimes he did share them but his partner can't cooperate with it. So they go outside to get it.

4. "I can't turn down sexual offers owhy men cheat on their girlfriendsr invitations." He thinks that "he is not a man" if he turns down sex, especially by someone attractive.

5. "I have low self esteem". He feels flattered and his self esteem is boosted when he finds out someone else is interested in him.

6. "My partner doesn't make me feel special". He cheats because he thinks that someone else can make him feel special and fill this gap.

7. "I can't really commit to anyone". He has a damaged sense of commitment, although he would probably deny it at first.

All of these reasons for your man cheating have one thing they common: They all think that going outside the relationship will fill their needs and solve all their problems. Most of the time, these are not the real reasons but only the justifications cheaters make to make sense of their betrayal for you and for themselves.