Hey OP, it’s so impressive how you’re dealing with this.
Well done for checking the car. Sounded nerve-wracking! Don’t feel you’ve done anything wrong. Given you’re his wife and share a home and your finances with him, it’s hardly an unreasonable thing to do. And it appears he’s been emotionally/financially abusing you for years.
Don’t give him the satisfaction of the expected argument. Remain calm and aloof. Let him explain himself, then say you want to think about what he’s said and remove yourself.
Reading your threads, it seems your DD’s equally disdainful and disrespectful behaviour is likely learnt behaviour from her father. Did it get worse when the other DDs moved out and the three of you were left? With her increasingly ‘siding’ and joining in with your DH?
No doubt, her behaviour towards you is appalling. Especially while living rent free and being looked after like a child in your own home. But try not to think too badly of her. The blame lies solely with your DH for setting her such a poor example in how to treat/disrespect you, and encouraging her to be his ‘ally’.
His behaviour is likely so normal to her that she’s at risk of similarly unhealthy relationships, including choosing a partner who treats her badly. Because she’s witnessed that happening to you as her female role model.
By remaining calm, while making it clear you won’t tolerate any more disrespect, you’ll start to undo the damage. It’s the best way to teach her women shouldn’t be (and shouldn’t tolerate being) treated like that. Show her lots of love and there’s far more chance when you divorce (as it seems you must) she’ll become closer to you and you can both heal together.
But for now set boundaries (don’t be her slave) and don’t trust her. Change your passwords immediately and don’t leave anything in the house while you’re at the spa that your DH could use in a divorce. It’s still possible there’s an OW and there appear to be debts (credit cards).
I strongly suggest you read about emotional abuse and seek some counselling via a local domestic abuse agency to help you process everything. I still struggle to admit that’s what I experienced. But being told that’s what it was, along with the support/counselling I received, certainly made me realise the behaviour was unacceptable and I should expect better. So I left.