"I sleep away from you."
Translation:Eu durmo longe de você.
I assume the English intends something along the lines of I'm travelling and staying over night away from my spouse. However, I'd probably use the word 'apart' in the sentence, not 'away'. If I was sleeping on the edge of the bed facing away from my spouse who was on the other side of the bed, I might almost say that phrase. Almost.
Only if you're in a region of Brazil where "tu" is used as the informal you (or in Portugal), and you're with someone with whom you feel like you can be informal with: a friend, a close relative, a romantic partner, etc.