Yeah, it's easy to stop because it's just, you know, not saying a word. But it's hard when this is the word that has been plugged into a cultural space in our language. I don't have that habit with "retarded," but I do with "bitch"-as-a-negative-term, such that I'll hesitate or stumble because I don't want to use it, but I that's the word that comes up first.
So anyway, I'm going to try to say "don't use this word." Iiiff you have other suggestions of ways to say that which don't anger or alienate, I'd be happy to hear them.