In my experience, when anyone has ever said "lucky you" or "good for you" in person, it has always been said in a negative way.

Because of the way in which I have heard people say that phrase, I have interpreted it to mean : "F*** you and go away. I hate your guts and want you to d**". For me, that phrase has usually been followed by violence from the person saying it, so it invokes fear in me. That is why I responded in the way that I have. I have never experienced someone saying either phrase in a positive way. "Lucky you" and "good for you" are both phrases that are dismissive and phrases people usually say if their intention is to hurt the feelings of the person they say them to.