Praise be to Allah, The Lord (The One and Only) of the worlds. Blessings and peace be upon our master, Prophet Muhammad, the Truthful and the Faithful.
A Muslim will not be held responsible for the entire Umma, but he is responsible for three areas (circles): His own self is a circle, his home is a circle and his means of living is a circle.
This does not mean that you can't be a great caller to Allah, establish a charity institute or do other million good deeds from which the Ummah may benefit, but you will be held accountable only for the three circles you own.
Being responsible for these three circles is Fard Ayn (refers to legal obligations that must be performed by each individual Muslim).
It is not acceptable that your wife does not abide by the Islamic dressing code. It is not acceptable and right that you abide by Islamic rules while your wife wears short tight dresses.
Islam is a whole concept, it is about circles of responsibilities, thus your own self is a circle, your home is another circle and your means of living is a third one, simply because the decision is yours in these areas and you have the ability to say yes or no.