Let's look at what Scripture has to say on the matter, the end of the world that is.
1 Thess 2v2, 'not to be soon shaken in mind or troubled, either by spirit or by letter, as if from us, as though the day of Christ had come,
vs3, 'Let no one deceive you by any means, for that Day will not come unless the falling away comes first, and the man of sin is revealed, the son of perdition'
When was the man of perdition revealed?
Also, in 2 Peter 3v10 it tells us that the heavens will pass away with a great noise, and the elements will melt with fervent heat, both the earth and the works that are in it will be burned up.
That will happen, but when God says, and God will destroy both the heavens and the earth, not just the earth.
This is nothing to worry about.
As it says in Revelation, he who is unjust, let him be unjust still, he who is filthy, let him be filthy still, he who is righteous let him be righteous still, he who is holy, let him be holy still.
In other words, who is saved when the world ends is saved, who isn't, isn't.
But for God's glory, we need to reach the lost.