Yes, believers are to be different from the world; in fact "worldliness" is a term that needs to be revived among Christianity. However, what gives a person power to live a holy life?
What is the crux of Wesleyanism? What is the power of holiness? What is the definition of Christian Perfection? It is realization that God wants to flood the heart with his love.
Love is patient and kind; love does not envy or boast; it is not arrogant or rude. It does not insist on its own way; it is not irritable or resentful; it does not rejoice at wrongdoing, but rejoices with the truth. Love bears all things, believes all things, hopes all things, endures all things. Love never ends. (1Co 13.4-8 ESV)Wesley believed that the result of being perfected in love meant that a person loves God with all he's got and also loves his neighbor as himself.
As Wesley shared in A Plain Account of Christian Perfection:
I think it was in the latter end of the year 1740, that I had a conversation with Dr. Gibson, then Bishop of London, at Whitehall. He asked me what I meant by perfection. I told him without any disguise or reserve. When I ceased speaking, he said, 'Mr. Wesley, if this be all you mean, publish it to all the world. If any one then can confute what you say, lie may have free leave.' I answered, 'My Lord, I will;' and accordingly wrote and published the sermon on Christian perfection.Love is gloriously contagious and contagiously glorious! Who can be against such a doctrine?
I love this prayer of Paul:
and may the Lord make you increase and abound in love for one another and for all, as we do for you, so that he may establish your hearts blameless in holiness before our God and Father, at the coming of our Lord Jesus with all his saints. (1Th 3.12-13 ESV)Is your love deficient? Can you say that your heart has been perfected in love? Can you say that your heart is blameless in holiness?
Pray for love.