Husband is a gambler and it’s affecting my daughter

My husband is a gambler. We remortgaged our house to pay off  his debts 3 years ago.  All his wages goes into my account now and I transfer a set amount back monthly. Not ideal but we agreed to do this. I look after all finances now. 

we have 2 children. My eldest now 15 has been badly affected by this and has needed counselling. My husband used to leave them at home to go out and gamble. Then we remortgaged a few years back to pay off his debts. He now works from home and I recently discovered that he is gambling again but online. And it was my children who told me as he has been asking them for money and telling them not to tell me. My daughter feels torn. It was her counsellor who told me this (with my daughters permission of course) . So now I feel like I’ve let my children down by not protecting them. 

my daughter will be doing her GCSEs this coming year and I’m worried for her mental health. The counsellor will also be in touch with her school. She has a lot of resentment towards her dad.

my husband is in denial about this. 
I’m dreading talking to him about this as it always end in an argument. 

I just wanted to know if anyone else has been in a similar situation and how you dealt with it?

After we remortgaged, I told him we would get a divorce if he ever gambled again. And now he’s gambling again. I know he’s in debt as he is always complaining how we can’t afford anything etc and he never has money to spend on my birthdays and special occasions etc plus I noticed he opened another bank account but is being very secretive about it. 

I feel so worn out now and resentful towards him.

any advice would be greatly appreciated. Thank you for reading this.