I don't know that I want to live forever.
Forever is a really long time. Maybe the Big Rip happens 22 billion years from now or the universe avoids the Big Rip and suffers the Big Crunch many billions of years later or the universe suffers heat death sometime around the year 1 Googol.
In any event, we're talking really long timescales.
I would love to see, as the centuries, millennia, and megannums pass, the Andromeda Galaxy grow ever larger as our galaxy, the Milky Way, and far-off Andromeda are drawn ever and ever closer. Sometime in the future, some estimates suggest between three and five billion years from now, the Milky Way and Andromeda Galaxies will collide. As collisions go, this will be a largely painless collision; galaxies are largely empty space, and the two barred spiral galaxies will basically turn into an elliptical galaxy once the two galaxies coalesce into one. Some arms, perhaps our own Orion Arm could be ejected from the Milky Way and become its own detached thing, much like the Magellanic Clouds appear to be shattered remnants of devastated galaxies.
This cosmic collision, when it happens, will be near the end of our sun's life cycle. Wherever the atoms that comprise us and everything around us today end up in that time of celestial upheaval, our solar system won't have much time, on a cosmic scale, to acclimate itself to the new status quo.
I'd love to see it, though. To watch two galaxies approach, wrestle, collide. To see things on a scale of time and space that the human mind can barely comprehend.
No, I wouldn't want to live forever. Forever is a long, long time. But to see the collision? Yeah, I'd like to live long enough to see that.