Perhaps. Is he truly repentant or do you suspect he is a serial cheater? In some cases, forgiveness is in order. It really depends upon the partnership two people have created. That's where a woman must look at the pros and cons of staying versus leaving. Many couples are able to sustain a relationship even if one partner cheats once. Trust can be rebuilt over time. Needless to say, the ground is very shaky in the beginning stages of "trying again." Go with your gut and set your emotions aside, even though it's hard not to see red!
Having said that, it is important for women to know that only about 20% of men remain absolutely faithful. That's one of the reasons why I urge women to be very selective about whom they choose to date (or marry).
Long story short, it depends. One needn't always throw out the baby with the bath water.