Try talking to people outloud as if they were there....Perhaps that may sound ridicoulous and yet it helps me to get out my frustrations and have a good hearty laugh. It also helps get the words out right. SOmetimes it is easier to plan out how the conversation is going to go then to go in without any thoughts. There are books I am sure to help. You are not that specific in what you wrote in like is it a social situation? Does someone ask your opinion on something and you offend them? Or is it in casual conversation? Sometimes it may be best just not to say anything too....I hav ethe same problems....