Concerning the phrase "forever and ever" found in the verses of Revelation 14:11 and Revelation 20:10 would more accurately be translated as "to the ages of the ages".
Young's Literal Translation bears this out:
and the smoke of their torment doth go up to ages of ages; and they have no rest day and night, who are bowing before the beast and his image, also if any doth receive the mark of his name. Revelation 14:11
and in Revelation 20:10 :
and the Devil, who is leading them astray, was cast into the lake of fire and brimstone, where [are] the beast and the false prophet, and they shall be tormented day and night -- to the ages of the ages.
Now, an age is generally thought to be right around 2400 years, I think, but these verses say: "to the ages of the ages".
Rather than those being in eternal torment, the phrase, to me, means: beyond what we can see... an indefinite period of time. This doesn't mean eternally, for ever and ever, but is rather more than we can personally perceive, know, or be sure of it's duration.
I would tend to think that any amount of time being in torment, or being tormented, would seem to be never ending, and ever lasting, but I do not think that that is the intention of the verses.
Ever have a parent ground you without a given time for the end of your punishment? That they just said: "I'll let you know". That must have felt like an everlasting punishment, when it was actually just unknown when it would end.