the capacity to forgive and the liberation of forgiveness is
amazing...
don't doubt love... if she really loves him and he is really
repentent, then it's forgiveness that is liberating for the both of
them isn't it? 
he, learns his lesson and will never even think of straying
again...
she, in giving him forgiveness, earns his everlasting
devotion...
and if the both of them work this out and are truly loving, there
could be a strong and wonderful bond to be made...
someone once said this: a relationship is like a string.. if it is
broken, and can be mended, the string becomes shorter and both
sides become closer...
as for love, again, there are no reasons to it...
just like there can be horrible monsters out there, there can be
wonderful, loving and faithful unto death and beyond men out
there... and all those in between with their baggage and
weaknesses...
your guy may be one who will be insanely faithful.. so don't look
at others and their infidelities, and then forsake him for
something he has not done and will never do?
sometimes, love isn't enough to hold a couple together... why add
the weight of the world to it?