As the spouse of a retired AF nurse who is now teaching nursing, I would suggest you think carefully before trying to do a language along with nursing. Nursing is difficult, there is a lot to study, and you'll have labs and clinical outside of class time. Plus, I don't know about the school you chose but some nursing schools don't admit into the School of Nursing until junior year and there are strict GPA requirements. But if you're doing a language you can go with what the AF wants and try Arabic. It might help you if you're deployed in an area that speaks that language or possibly for a humanitarian deployment. If you think you want to do post-military work with an NGO like Doctors Without Borders, then Arabic would be good. If you think you'll be doing nursing in the southwest post-military, then Spanish would be helpful.
As a career aside, she went into the AF as an L&D Nurse, then the AF sent her to get her Masters in Nurse-Midwifery and she finished her career as a Certified Nurse Midwife. Friends became Nurse Practitioners and became providers. And some became Certified Nurse Anesthetists. There are lots of good career options in Nursing. And it's a good AF career to take you overseas if that's what you want (we had tours in Okinawa and Germany). Good luck!