What is the proper way to decline an invite for thanksgiving f/ someone u don't no and just want to be alone ?

I am a college student, so all my family is out of state and the family I do have here will be gone along with all of my friends from school. Someone I know told another person of me being alone on thanksgiving. I am totally excited for thanksgiving alone I see it as an opportunity to rest up before finals and I am not feeling good. So back to my question how do you respectfully decline and invite from a teacher whom you have never had and don't know?