Please don’t judge yourself so harshly. We all make mistakes, and as long as we learn from them they are simply lessons. Your co-worker made the mistake of disrespecting his wife and their marriage, and you made the mistake of being with someone who was not available to you. An error of judgement does not make you a bad person, it makes you human. Have compassion for yourself and try and look at the possible good that can come from this situation; you have learned a valuable, if painful lesson. If your co-worker’s marriage was as much of a fairytale as he likes to paint it, why was he unfaithful? Perhaps the thought of losing everything he already had gave him a renewed appreciation of what he was risking but this is absolutely NO reflection on you; rather, this was his lesson from the experience. Be kind to yourself, reflect on what good you can take from the lesson and move forward in the knowledge that you deserve to be treated with far more respect than your co-worker showed you or his wife.