When people talk of life extension and us eventually achieving immortality, it is always "relative immortality" though. Maybe we develop the technology to regenerate our bodies and we could live for thousands of years. Maybe we can transfer our consciousness and minds into computers and maybe live for quite a bit longer than that.

But the time scale of the universe is unfathomable. Even if we lived for millions of years, it would be a drop in the bucket. And that time would still come to an end and we'd reach that same state of eternal nothingness and nonexistence.