How do I heal this hurt?

TLDR; My husband caused a lot of hurt last year (no cheating but a lot of hurt was caused by treating me like I didn't matter). He has now woken up and is doing everything right but I can't let my defences down and we are having weekly blowups. How do I repair the hurt to be able to validate his emotions and not just be defensive in arguments?

My husband started a new job last year and there were a lot of red flags and he started treating me like I didn't matter - shouting at me for asking how his day at work was, sulking when I asked why he was secretly taking 2 phones to work and getting angry at me for asking, getting caught in lies, being late home/missing an important meeting and not even apologising.. He stopped asking me how my day was, was constantly on his phone and was hiding his screen, getting angry if I was asking who he was messaging. I was trying to be the bigger person and asked rather than snooping but then obviously I'm the paranoid one for asking and getting upset when there's no answer and just accusations...

There was no cheating (I know I sound naive but I have now got the truth - he got into a new "lads lads" group at work and his anxiety to fit in meant he was saying unsavoury things about me and it rubbed off on his actual behaviours and was trying to hide the things he said) but the things he said and the way he acted hurt. So now obviously I am an anxious mess and he's trying to make up for it but still won't let me see the messages, gets mad at me for being anxious when he's late etc.

But this hurt is getting in the way of me understanding his point of view. In my anxiety, I have become someone else I don't like with snippy comments and anger but I try to contain it as best as I can. But I struggle to validate because when I do something wrong, it's in direct reaction to something he did. Everything I see to fix a relationship says to validate the other without being defensive but I can't do it.

Some examples:

I got a promotion at work and rather than saying "congratulations", he sulked and said he didn't like that I would be earning more than him. So now I go to my mum with good news as she was so excited for me. Husband then asks me not to go to my mum with news instead of him as it hurts. All I could reply with was "I'm sorry you feel that way. BUT it's because..."

Husband ignores me as he's on his phone and when I ask who he's messaging he says no-one and puts his phone away. Then ignores the buzzes until I catch him checking them in the kitchen. I then say my anxiety is playing up and could he please show me the messages. He says no because I need to get hold of my anxiety and it hurts that I don't trust him. All I can say is "sorry it hurts. BUT if you hadn't..."

How do I stop that "because/but"?

I understand it sounds bad (because it is) but he is trying. He says he's afraid of my reaction (which is understandable as I have been very strongly reactive in the past year) so is easier to not tell me so I don't get hurt.