Wise words, I do however think that any emotion can be ingrained to feel comfortable. Fear, sadness, anger, any of them. It seems odd to think of certain emotions (like fear) as being comfortable, but a person may retreat to these emotions so frequently that they become the norm. A familiar retreat into the comfortable reality of their lives. I am not trying to sidestep your point here, but I wanted to bring up a big picture perspective that all emotions are meant to serve only as the purpose of a signal to us. Anger tells us a boundary has been crossed, fear that we are threatened, sadness arises when loss is present or perceived, and shame occurs when we are not in accordance with our own morality, or rather, with the identity of self we believe we are supposed to portray. None of them should be comfortable, they are just physiological signals that inform us as to how our core self (identity, image) is responding to the current situation. Even happiness is not meant to last, it was designed to spike at a moment of enjoyment but then it must drop back to the norm. If it didn’t then we would loose our ability to gauge whether or not a situation makes us happy. Our emotional perception would become distorted, and that can have negative effects in our life.
I re-read your original post and I think we are saying the same thing. I just needed to reword it in my own long winded perspective. Does this sound like what you were saying as well, or did I miss your point entirely?