I'm thinking of refusing to share my extra income with my wife when she didn't share hers with me when she earned more
Do you two have separate accounts?
Yes, she was greedy and refused to get a joint one.
Partners don't always have to share accounts. As long as you share equally in the bills, if you both have paying jobs you can still keep most of your finances separate without it being a problem.
You're right.
You shouldn't expect to share everything if someone has a budgeting problem. You should probably talk to her about saving for retirement and big goals like a car or a home,