My job is going to do everything in their power to make me quit instead of firing me, any advice on how to gain some mental fortitude?

I’ve been so burnt out and my physical/mental health has deteriorated since I joined the job. I’ve been gaslight and played like a fool. They’re going to insult me, yell, and etc… into making me quit. The severance is 6 weeks, so I’m definitely not leaving until I get that. Any advice on how to deal with this?