Actually Hitler tried to invade Russia because there was no way in hell Germany could support their war against the UK without new resources, especially fuel.
Of course at the time he thought that people would rally against Stalin (because like you mention Stalin was not an angel either).
He forgot one thing, love for the "motherland" goes deeper than loyalties to any particular leader/party (ie communists/stalin), funny that Hitler overlooked this because one of his own generals (Rommel) loved Germany but didn't like the Nazis.