I go for the colour as feeling explanation, like the "blues", but expressing a different feeling entirely.
I interpreted it to be feeling grey, by which I mean feeling really apathetic, like when you're really tired and you just don't give a shit any more, or the way that emotional experiences generally appear to get less intense as you get older.
"The greys flood our memories in the long haul", and "Can these greys wash away?" make sense if you read it like that.
I think that "The greys" being a species of alien is coincidental, or secondary.
That's my interpretation anyway, take it as you will.
I interpreted it to be feeling grey, by which I mean feeling really apathetic, like when you're really tired and you just don't give a shit any more, or the way that emotional experiences generally appear to get less intense as you get older.
"The greys flood our memories in the long haul", and "Can these greys wash away?" make sense if you read it like that.
I think that "The greys" being a species of alien is coincidental, or secondary.
That's my interpretation anyway, take it as you will.