Does she take religious customs so serious? The bible says nowhere that you are supposed to not eat any meat on Ash Wednesday. That's an interpretation that was started much later (and in a time where peole didn't have much to eat and would eat meat only once a week anyway).
Also, Jesus himself got attacked by Jewish conservatives because he violated the Sabbath customs. Isn't that a sign that he didn't think such customs and rites important?
IMO what counts is to be a good person, not to stick slave-like to some rather dusty rules.
How about taking her out tonight to a really nice chicken restaurant?