Lazarus and The Doctor in “The Lazarus Experiment”

You're so sentimental, Doctor. Maybe you are older than you look.

I'm old enough to know that a longer life isn't always a better one. In the end, you just get tired. Tired of the struggle, tired of losing everyone that matters to you, tired of watching everything turn to dust. If you live long enough, Lazarus, the only certainty left is that you'll end up alone.

That's a price worth paying.

Is it?