We are not responsible for the happiness of a human being.
Real love loves without exception, period.
Your husband is blaming you for his own misery and inability to create his own happiness. There is nothing you or anyone else can do to "make him happy"... Only he can do that with how he chooses to manage himself.
Don't fall for the lie and wonder what would have happened "if you just... (fill in the blank)". It would not have made a difference.
By blaming you, he does not have to hold himself responsible for his own actions.