This is really hard for me to rate.
On the one hand: it is a terrible game.
It works, but it isn't particularly fun.
But unlike most games: it is actually intended to not be fun.
It is intended to be more of a simulation, and that it achieves pretty darn well.
My first gripe is that the food thing seems to do nothing.
I can't tell in any way how badly I need to eat.
I have sound turned off on my computer, so I don't even get an indication that I ate.
Then again, the character in the story is going crazy,
so I guess that's not really important either.
My 2nd gripe is that you took the treadmill away so soon.
Maybe because I was starting to have fun on it? lol
Good job, I think you achieved what you set out to do.
On the other hand: I think it is more from an extrovert's viewpoint.
If you're going to send someone out into space alone: don't send an extrovert.
Send an introvert, that is more comfortable with long periods devoid of human contact.
As such: I think you missed the mark a bit on this one.
Then again: this was not really about going into space,
it was more about us being isolated, and how that feels.
So I come back you: good job, I think you accomplished it.