Keep your head in a positive place. Catch yourself when you feel like replying to a thoughtless remark and reply with a very positive thoughtful response like “I appreciate your concern/point of view/question, could you please think of a less negative or derogatory way to let me know? When I hear it like that it’s hard to reply without being frustrated and I don’t think that was your intent.” Smile.
When you feel negative, Smile and do what you are asking your friends and family to do. Spin it around to a positive and focus on what you can do.