What helped me to cope with this Bible teaching is that Armageddon is said to come about as a result of the attack of 'Gog', and the 'king of the north' against God's people ( Eze 38:18-23; Dan 11:44,45 ). The Bible presents God as destroying the 'wicked' at Armageddon because of their attempt to wipe out his people. This 'reassuring' thought helped me a bit to come to terms with the prospect of the violent destruction of billions of people, although I did worry about all the nice old ladies that I knew, who would probably be hiding in their bungalows during the attack of Gog, rather than being out on the streets trying to duff up JWs, and yet they were still in line for 'the chop'.
It does have to be borne in mind that the Armageddon teaching is not the invention of JWs but comes straight from the pages of the Bible ( as does the disfellowshipping and shunning policy - 1 Cor 5:11 ). Being firm believers that the Bible is from God, JWs take the view ( as I did ) that God must know best, and that his destruction of the 'wicked' must be right. Even if the view is taken that it won't just be non-JWs who will be destroyed at Armageddon, but that it includes all people who don't practice Christianity, that would still mean that billions of people are in line for destruction at Armageddon. 1 Thess 1:7-9 says that: "The Lord Jesus Christ shall be revealed from from heaven...in flaming fire taking vengeance on them that know not God, and that obey not the gospel...who shall be punished with everlasting destruction." Clearly, the Bible portrays Jesus as bringing violent destruction on all non-Christians, all who 'obey not the gospel'. Is it any wonder that a staunchly Bible believing group like JWs preach the destruction of the 'wicked'? How sad that they feel they have to believe this breathtakingly, barbaric Bible teaching.