Answer: I think you’re overthinking how this reflects on her integrity, and under-thinking — and under-discussing — the nuances of "trust, openness, and honesty." It is by no means a slam-dunk that telling the whole truth is always good.
Kant posed the question of whether you’re obliged to tell the truth if a murderer came to your door and asked where your friend is (I hate it when that happens). It’s a great starting point for the idea that even good, moral people draw lines in the gray when it comes to telling the truth.
The implications when it comes to relationships and cheating surface often in this column, and I can’t think of an instance when people weren’t split roughly down the middle between thinking the unselfish thing to do is to confess a one-time infidelity (because people deserve the truth), and thinking the unselfish thing is not to confess a one-time infidelity (because the confessor feels unburdened at the expense of peace of mind of the confess-ee, who arguably is no better for knowing).
So, consider shelving the impulse to jump to dire conclusions about your girlfriend, and raising the issue again — but not as it relates to her or even your friend. Instead, bring it up as it relates to life and to the deceptively tough choices presented by a decision to take the high road.
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