Down Syndrome Then and Now

When I read some of your blogs, I've noticed there are some things that I do that might not be appropriate now. Please know my heart in this - the printed word can be written in humility, but can be read with anger or discust. I don't want to hurt or offend anyone and I'm afraid I might with my 'old fashioned' ways. So before I put my foot in my mouth, (if I haven't already,) I'd like to ask a couple of questions.

When Beth was born, the term Downs was often used and widely accepted. I still use it today, but it seems like it's not appropriate anymore. Why is it offensive?

The word retarded. When Beth was little, my mom rented a room to a mentally handicapped woman. She would often hang out with friends and one day her friend came over in tears. She said someone had called her retarded. The girl (early 20s) told her matter of factly, "I hear the word retard a hundred times a day. It doesn't mean anything to me because it's not true," and out the door she went.
I definitely understand not calling someone retard just like you wouldn't call them idiot or stupid but I'm not sure I understand the deep hurt that some seem to feel with that word.