...Rev 20:13-15
(13) And the sea gave up the dead which were in it; and death and hell delivered up the dead which were in them: and they were judged every man according to their works.
(14) And death and hell were cast into the lake of fire. This is the second death.
(15) And whosoever was not found written in the book of life was cast into the lake of fire.
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I don’t see they are destroyed, rather they are cast into the Lake of Fire.
Verse 20 though seems to describe the consequence of being placed in the Lake of Fire.
Rev 20:10
(10) And the devil that deceived them was cast into the lake of fire and brimstone, where the beast and the false prophet are, and shall be tormented day and night for ever and ever.
This indicates to me that the soul cast there isn’t destroyed, but is tormented eternally.
Rev. 20:10 talks specifically about Satan, the anti-Christ and the false prophet, it isn’t talking about those lost souls that were in Hell. It does appear that those three entities are tortured forever. Why? Maybe because they are made of different stuff??? I don’t know.
What I do know is that the second death refers specifically to the unsaved souls. If the eternal torment idea was correct then “second death” makes no sense because nothing would be dying.
Plus you still have the issue that in order to be tortured for ever, you would have to be alive for ever and in order to be alive forever, you would need to be immortal and the Bible tells us that only those who accept Christ as savior take on His immortality.