You would have if your wife's family made the assertion to the hospital that you two weren't legally married and that they were the true next of kin.
I'll tell you something I know for fact from first hand experience. A marriage license does not mean you will have full say in your spouses care if your spouse can not make the decision. You can not in some cases but the state can make them. I know because about 13 or so years ago I almost took my wife by force against ones who may have tried to stop me had it become necessary out of state for medical treatment because as her husband I was not allowed to make a critical decision. BYW I had signed for most of her care up to that point including surgeries.
She had an extreme adverse reaction to some medications which although she was conscious she could not make rational decisions. Because the attending ER doctor wrongfully determined without so much as a blood work testing and PDR look up of her medications to have a mental condition. At that point I was forbidden any treatment say and the state called in. A few days later I diagnosed her condition for them because I looked up the suspected medications on line. The condition being an extreme adverse reaction to prescription medication given her. However a Medical POA would have allowed for me too have that say even though a marriage license would not so the Fags argument for need of marriage to determine other "whatevers" care is actually Bogus. Anyone can give any other adult their medical POA.
On the other hand when her final days of life came a few months ago I signed the Home Hospice paperwork. I also signed for a Trach to be put in a few days earlier.
Our doctor told me individual states have laws as too whom has the legal say in a spouses physical care if no POA papers are signed. First is the patients spouse. Next is the eldest offspring of patient if age of majority then next one if same, after that comes parents.
I also signed for my dads permissions when he was dieing so Mom didn't have the burden placed on her. The Gay Mafia is using everything they can think of and blowing things way out of proportion too justify legalization of their perversion. Medical POA has been a long recognized writ. So much so hospitals encourage spouse to have them. Is there a law against designating anyone other than spouse of offspring as POA? No. A person can designate a stranger if they are agreeable.