The grass is greener on the other side
If the grass is greener on the other side, then the guy with the greener grass doesn't think your grass is greener now does he? The message that this proverb is trying to stumble through is that everything always looks more attractive when you don't have it. I'm sure there are millionaires crying themselves to sleep every night because they don't live in a trailer park. Just face it: sometimes nobody envies you. There has to be a bottom and that bottom is probably you.
It made me giggle.