His focus was always on the East. He attacked East. He did not attack West until Britain had already declared war on Germany.
Hitler really wanted an alliance with Britain. When they refused him, he considered it a slap in the face, and von Ribbentrop, also felt insulted by the Brits when he was the Ambassador to Britain, and convinced Hitler that Britain was his biggest enemy.
Maybe I should be more clear. If he had focused on the area around Germany, honored his agreement with Stalin (if only for a while longer), and built up his empire, he would probably have prevailed. In the end, he just bit off more than he could chew, at least in the timeframe he chose.