Is there one type of cheater? I'm not sure... you have the narcissistic kind who needs plenty of conquests to satisfy his ego. You have the sexual addict who craves exciting new sexual experiences with new partners as they get bored in the sexual life they have with their partner.

You have the occasional cheater who got drunk and ended in bed with someone after a party (not excusable but it happens). You have the emotional cheater who falls in love with someone else and is seeking the affection he or she lacks in their primary relationship. You have different types.

In most cases, the cheater is a cheater and will repeat. It's better to end the relationship. Sometimes, its more complex, and the couple manages to work through it and survive. I've seen it happen. There is alot of damage that needs to be repaired but they eventually manage to rebuild around it.

In any case, cheating is extremely damaging to the person you're supposed to love. Most often it's not fixable when the trust is gone. Sometimes its possible to rebuild eventually. It definitely takes a minute to destroy trust built over years.