I don't think the right word should be "girls" because both sex (males and females) are accusable of that act.
In my book, cheating on your spouse is a no no, i don't feel its excuseable
but that doesn't mean i'm blind to the fact that it does happen and sometimes due to circumstances we forgive and give the person a second chance
why?? because we're human and are liable to making mistakes once in a while, it doesn't make it OK but it sure helps you think straight after the anger has cooled down
I've come to realize that though someone says they love you, it doesn't erase their capability of hurting you, its their way of owning up to their mistakes and taking responsibility that counts
it hurts, i know but there's no perfect human being on earth.
it kills some of the trust in the relationship but its not impossible to re-build the trust

But if her infidelity would be difficult to forgive, as in him bringing it up every minute of the day or not being able to relax with her because the memory keeps flashing back or him worrying every moment "who knows what she's up to"? then i do advice they part ways, even remain friends but nothing more

if she heartily pleads for his forgiveness, and he can sincerely forgive her , its difficult but not impossible, then giving her a second chance is not such a bad idea
