My wife will be traveling with me to mexico.. I am nervous about the fact that they do not recognize same sex marriage, therefore if anything were to happen to me medically, would she be able to make medical decisions for me?? Anyone else in this situation?

Can't you bring a medical directive stating that she would be recognized as your power of atty if you were to become unable to verbalized your wishes?

You can assign her as your power of attorney. http://www.rocketlawyer.com/form/power-of-attorney.rl

All you should need to do then is have it notarized or signed off by an attorney. I'm not sure the law in your state, but this should cover you. I'd also call the surgeon's office and explain your concerns.