"Toxic" is an imprecise word I usually don't use or relate to. However, in the case of your home situation, it sounds like a good description. I don't see where you can ever be at peace in that household. It does sound like daily, round-the-clock toxicity. Your father sounds awful. Getting your kids and you out of dependence on being under that man's roof is the best move you can made.

Your father is a foolish man. As your mom's dementia progresses, he's going to need help managing her care. A live-in adult daughter would be the ultimate asset in that situation. Your father does sound thick-headed enough to shoot himself in the foot. He'll never change. In the parent-lottery, you were very unlucky. I'm sorry. No doubt, you bear many psychic scars from the dealings you've had with this set of parents.

Some people just have to have someone to abuse. In your parents' home, you got nominated and confirmed for that position. It won't change. I doubt your kids get much grandfatherly love from this man. Getting out of that home may be in their best interests too.

Life is requiring that you be exceptionally strong. The main thing I would hope for you is that you would find some source of support IRL. Perhaps a woman's group of some kind. If you were a domestic violence victim, or had a history of substance abuse, you could find agencies and groups that try to help people in those specific populations. It may be that there is no support specific to a woman in your situation. You may be like many others who fall between the cracks and get left to cope with little or no backup.

You are a survivor of what sounds like years of emotional and physical abuse. The threat of irrational violence from your father has been abusive. I wish society offered something that you could grasp onto because you sound very alone. Maybe there is something. Perhaps a large church may have some family support services. Make your next home your sanctuary for your kids and you. Find something in the community that you can participate in. You need friends.