Your boss is being nice to you

by giving you a chance to quit instead of firing you. So be nice to him/her. This is an employment at will situation. He/she can fire you for no reason. You sue him for what? for giving you a chance to quit?

Spend time and efforts on your job hunting. Giving the way you think and treat your boss, you deserve to be fired, not being given a chance to quit.

Remember, employment at will (as long as no racial discrimination, etc). There is nothing wrong with 明摆着新老板就是要建立自己的王国. President Clinton fired all US attorneys.