What a lucky lady. A 65 Stang for a present. Some people have all the luck. As for a name, I don't know how about Missy? That sounds a little sassy. About right for the car. good luck and happy anniversary.
I had a plain white 1961 Ford Fairlane I named after the original owner on the title. I was certainly an old ladies car. Check the title and see how far you can go back, if it was a woman, name it after her. My 61 Ford was named Mildred, it fit perfectly.