what key aspects of Ahab's early life do we learn when he discloses himself to starbuck

Ahab reminisces with Starbuck about the day when he struck his first whale nearly forty years ago when he was only eighteen. Ahab laments the solitude of these years, only three of which he has spent on dry land. He claims that when he married his wife he immediately left her a widow and says that he has "foamingly" chased his prey as "more a demon than a man." Ahab questions the strife of this chase. Ahab finally says that "toil we how we may, we all sleep at last on the field" and "rust amid greenness."