Scripture actually spoofs the very idea of having nothing to do with people of the world due to sexual immorality.
1Co 5:9 I wrote to you in my letter not to associate with sexually immoral people--
1Co 5:10 not at all meaning the sexually immoral of this world, or the greedy and swindlers, or idolaters, since then you would need to go out of the world.
1Co 5:11 But now I am writing to you not to associate with anyone who bears the name of brother if he is guilty of sexual immorality or greed, or is an idolater, reviler, drunkard, or swindler--not even to eat with such a one.
1Co 5:12 For what have I to do with judging outsiders? Is it not those inside the church whom you are to judge?
1Co 5:13 God judges those outside. "Purge the evil person from among you."
Notice that Paul wrote not to associate with sexually immoral people, however, he specifically did not mean sexually immoral people of the world, because it's impossible to be in the world and do that.
We are not to avoid the sexuall immoral of the world, nor the idolaters, greedy and so on. These people are actually our mission for being here.
It is within the church that we do not have anything to do with the immoral. Those who claim to be Christians but whose lives are filled with sin, those people we are to discipline and have nothing to do with if they do not repent. But those outside the church, we are here clearly told that we are not to avoid them.
That's a case closed. God has spoken.
Marv