Its abuse op.
If you find yourself feeling like you cant even think straight in a relationship - you are being abused.
He is angry when you say you are fine because he doesnt want you to feel fine.
He constantly asks you if you love him because abusers want us to be stuck proving our love/trust/loyalty or innocence. Probably so that we focus on ourselves and changing our behaviour so much that we arent paying attention to the fact that their behaviour is not ok.
He needs to blame someone for everything that goes wrong in his life because he is a narcissist that cannot take responsibility.
He went out drinking when your mum passed because he doesnt care about you. Infact, it may even have been to punish you for being sad and therefore giving your attention to something other than him.
You say its difficult to get over. WHY should you be trying to get over such cold heartless behaviour from him?
Why are you trying to appease him? He is vile. And I'm sorry but, he hates you. Look at his actions and you'll see they show this clearly.
He is an abuser and he will never change.
You say you are strong - then be strong and leave. You cant win by challenging him or changing your behaviour to appease him or any of that shit. Because it's his game and he will constantly make the rules and change the goal posts.
Get yourself and your kids away. Or they in turn will partner with abusers as the grow up. Break the cycle, stop playing his game - run.