We've had the same problem. I've pulled up 3 better boy tomato plants and 1 Roma. Started over with seedlings and seeds. The seedlings are beautiful, about 3 feet high, and loaded with blossoms and a few baby tomatoes, except today I found one of the plants has started the wilting process. I hate to do it, but I will have to pull this one up to.

I received a suggestion that I need to pull out the dirt where the plants were, replace with fresh dirt and start over. It sounds like that is what I will have to do. Good luck to everyone.