A Strong Female!

In Macbeth the superceding character is Lady Macbeth.  A woman.  Why is that Shakepeare chose to present this story this way: A male soldier manipulated by his wife?  Emascualted to do her bidding.  Of course today we see it all the time, however was this not frowned upon during Shakespeare's time?  No offense to any woman but why did Shakespeare decide to portray Macbeth as a coward and Lady Macbeth as a gorgon?