The reference to eternity in afterlife doesn't mean "very long time"; it means "no time", a world that has no time. You can briefly feel the difference by being present in the current moment.
Eternity in its proper sense belongs to God alone; human beings sharing in "eternal life" will experience time differently. Even the angels experience "aeviternity" which is unique to their kind.
Could be; I'm not too literate on this, I'm only retelling what I understood directly and this could be very limited. I just wanted to point out that "eternal life" is not going to be the same life we have now, only endless. It is very different and, speaking of boredom, definitely not boring. Boredom is an invention of mind.
https://www.newadvent.org/cathen/05551b.htm
Eternity in its proper sense belongs to God alone; human beings sharing in "eternal life" will experience time differently. Even the angels experience "aeviternity" which is unique to their kind.
https://www.newadvent.org/summa/1010.htm#article5