Not being funny or anything, but if I lived to be 1000 I think I'd be incredibly bored. Imagine collecting your pension for 930 years :/ That's a lot of time in the Post Office.
We'd work a lot longer than 70 years.
Why would we get bored? Surely if people say you'd get bored over a stupidly long period of time, we'd have people committing suicide over boredom in mass numbers right now? We all have our own routines, with the same repetitive activities that we do day by day, week by week. Why is repetition not boring over 80 years, but it is over 1000? Surely we all live because of life, not out of "fun"? People who live under dictatorships and seek asylum live awful lives, with no "fun" in them but yet they keep going. It's easy to say you'd get bored and want to die decades before you're faced with your own mortality, but when it comes down to it, how many people could physically do it? The world and life is always evolving, there's always something new around the corner, when faced with it you eliminate the possibility of experiencing that, because it would truly be over.
I firmly believe that when faced with the decision; very, very few people could actually truly end everything.