Are you saying no insurance for rehab? Look into the Salvation Army, I'm in Canada and they do have rehab which I think is free. It would likely ease his guilt if he offered her the choice of rehab or out of his house. It's up to her and he should stick by his ultimatum.
Suggest to him that he get an ACOA counsellor. He needs a support system, this is alot to take on by himself.