Everybody needs friends, we all need someone to talk too outside of our home, friends are good for us and a submissive wife needs friends, she has the freedom to choose her own friends, but she should be careful who she chooses to be friends with.
Beings friends with people who tell you how to live your life or criticise how you live your life are going to cause you problems and these people should be avoided.  It is OK to have friends who do not understand your lifestyle but they should respect that it is your choice to live the lifestyle and they should not try to influence your decisions.  

Friends that constantly moan about their husbands and are always belittling their husbands are good people to be around, it is better to surround yourself with like-minded people.  

If you have a friend that criticizes your life explain to them that you are happy and it is your choice on how to lead your life, tell them if they do not respect your views then you will no longer wish to be friends with them, a true friend will respect your wishes and they are worth their weight in gold.