This isn't very specific information. As i mentioned previously, you'll probably want to use MVC to put your application together.
Also don't feel obligated to use a specific pattern. As you've found out when you tried to shoe horn your application into the visitor pattern which didn't work as expected. Why can't you modify your app to work with what you already have? Patterns are general guidelines, just because your code doesn't match the textbook definition, doesn't mean you can't tweak it.
If you do tweak the visitor pattern a little to fit, let us know what you did so we can check it out and possibly add it to our Pattern Catalogs
Here's a bunch of patterns you can sift through online pattern catalog. Please check this
link
Albert