You should understand if your wife had been the only bread winner in the family, or did a major part in supporting her family, it is not correct for you to stop it just because you married her. there are several questions to be asked.

1. Is your wife working?
2. If she is working, can she spare some of her income for her family?

If she is working, it is decent to let her spare a certain part of her income for her family. But, if you are the only income earner, you have the full right to decline it