My in-laws live with us since the last 25 years. My MIL has dementia and is heavily dependent. My FIL has been very instrumental in caring for her. However he is extremely opinionated, very controlling and dominating. He does not respect women and I find him very rude. He finds me rude because I do not allow him to constantly character assassinate me or provide me with 'feedback'. It causes major stress for me. I find it difficult to improve anything for my MIL and also my own mental health suffers when I interact with him. Moving them out is not an option as that doesnt agree with my ethic. How do I find peace? This is really affecting my husband and I.
Kick him out.
Why is that not an option?
You and your husband either lay down the rules of behavior in your OWN HOME or you tell the entitled in laws they have to leave. Immediately. It's that simple.
Well, if your ethics won't allow you to place them somewhere, I don't really know what you can do. Where is your DH in all this? Why has he not put his father straight about the way he talks to you. Its your house your rules. Look up "Grey rock method". Maybe you will just need to block him out. Pretend he isn't even there. Do what you need to do and walk away.
Has he always been like this? If not, maybe he should have a good physical, mentally too. Maybe stress from caring for his wife is causing him to be this way. Remember though, she is his wife and his responsibility. Do not allow him to make you feel her care is your responsibility.