How do I get this to work?

I've read every book and tried every method. I've tried staying in the room, I've tried leaving the room, we have a bedtime routine and a phrase that we say, but he just gets more and more upset. It's 5 am and he's been screaming since 3. I fed him. He's not wet. He's just angry screaming. He's the absolute worst sleeper and I can't not sleep anymore. I'm a sahm and my husband is up all night every night with us, which he also can't keep doing. It's been months since we've slept. We've even had mil spend the night to give us a rest and I'm still up all night breastfeeding and listening to him scream. He's not hungry, he's not sick. He's just pissed and I'm so tired and done 😪