Wow- someone sent you a PM because you posted about how you did NOT lose your cool when confronted with someone who was behaving in a very irritating manner? Really?
Well my take on this is that you did very well indeed. You are not denying your (totally understandable) feelings about this person's behaviour. You did not hurt her feelings by telling her that she was being a silly know-all, or even try to put her down with some sharp remark highlighting that you know more about quilting than she does. Instead you chose to stay cool on the outside and let out your feelings (and see the humour in the situation) with fellow quilters on an anonymous board. That sounds to me like a very healthy way to deal with it. Well done. I am firm believer in seeing the ridiculous in these situations!