Just because you empathise with another person or feel sorry for their life or even understand their reasons doesn't mean you condone adultery. There is no stain on you as a person for feeling for another human being. We are human and things do absolutely get to us. No need to feel apologetic or afraid that your own values are being corrupted because you feel for another person in a bad situation. In fact if you do not feel for other people that is a far worse sin in my book then holding on to your values.
Always remember you're not in that person's shoes and you will never understand another person or be able to truly feel why they make the choices they do and making judgements and deciding their fate without suffering their problems is both cruel and unkind.
I love these types of dramas because they depict what goes on in so many of our minds. We are not above wanting things in our life and happiness too. We stay married for reasons others cannot comprehend and cope with life the best we can without going mad. We shouldn't condemn others because we are stronger than them nor should we try to preach when we have not faced their problems or social conditions. In some societies a woman will lose her children when she gets a divorce. In that kind of situation why would any woman seek a divorce over having an affair. Life is so complicated and not as simple as some people makes it out to be.