No, not all men do.
I want to give you a hint: as long as the relationship stays fresh and exciting, there is no need to go and look somewhere else.
The moment a guy feels limitted and conscricted within a relationship, he'll tend to go and look somehwere else for "fresh inspiration".
If you deal with a cheater, get this e-book:http://vitalcoaching.com/relationships/ ... on_you.htm
It's spot on the cheating issue - specially designed for women
good luck and stay in touch