I would say that there is something he is spending money on that he is hiding from you

It could just be that he has more debt somewhere that he won’t admit to. He is probably ashamed of it so he does not want to admit it. My partner and I are working on similar issues except that our situation doesn’t sound quite as bad. It’s more that she is embarrased by her level of debt, but money back from insurance would not be spent without giving it to me. Joint money is joint money and she respects that. It’s more about her individual finances that we are struggling, but we are making progress.