The problem with Adam is that he’s struggling through deep depression. Adam refers to modern humans as “zombies”. He is disgusted by them because they have infected their blood with drug use and unhealthy diets. Most human beings are so unhealthy and infected, that for a vampire to drink their blood is to risk becoming terribly sick. Adam is also too much in love with the past and nostalgia. He is unable to deal with most of modern culture or media. This is why he stays alone in his house at night, just sitting there in the darkness, brooding and contemplating what has been wrecked by the modern world.

Eve: “What is it, you look tired.”

Adam: “Do I? I guess I am. Yeah.”

Eve: “… So what is this then? Can’t you tell your wife what your problem is?”

Adam: “It’s the zombies and the way they treat the world. I just feel like all the sand's at the bottom of the hourglass or something.”

Eve: “Time to turn it over then.”

By Adam making this statement, he is simply expressing his disgust that he is immortal in a world that he doesn't want to be in anymore.

..all the sand is at the bottom of the hour glass

Time has run out.

An hourglass (seen below) contains sand that runs from the top to the bottom through a small hole, over a fixed period of time.

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