I got my Camaro restoration done just in time for the wedding. Two weeks later she was on my case to sell it. I finally gave in for the sake of peace in the family. I practically gave it away and have regretted it ever since. Six years later I bought the '47 panel. She had some REALLY NASTY things to say. I mean, like PMS on steroids! I told her I was no longer going to allow her to get away with emotional terrorism. I called her a bully. (She had a pretty well established pattern by then.)
We were already in counseling at the time, and this gave us plenty to talk about. A year later, the truck is still here and she is much nicer to live with. Counseling ain't cheap, but it's worth it.
If you are spending all your time on the truck and ignoring her, she may have a leg to stand on, but if she's just trying to rule the roost, she is out of line.