ok, so you know you love her and don't want to leave her, yes your mad at her. When she did what she did were the two of you saying i love you yet? Were you two taking bigger steps towards a deeper relationship? If the two of you were in love at the time it happened then I can see how you fee like shes getting off easy. You said that she deleted all her male friends without you telling her too that's good. And at any rate was she really talking with the other male friends any way? or was it an occasional email, or an update letter on how the two of you are doing.
But if you know you love her and don't want to leave her, you know she wont do it again, then don't let this rein your relationship. and try not to drag you relationship worrying constantly about it or their would be NO point in staying in a relationship that causes that much stress.