This is a case of blackmailing and molesting emotionally. You should take charge to stand for yourself and raise your voice against this cruelty. No one can ask you to resign without any bold reason and you should not resign instead you should stand and fight back. You can take this matter to the whole office staff and ask them to clarify whether your boss is doing right or wrong. You must speak up and ask for your rights at the workplace. 
You are an employee and you should be respected in your workspace no one should venture into your position to demolish for the sake of fake blame games. Stand up against wrongs and protect yourself.