I live in Burgundy. There are a lot of very nice romantic places around here. And several castles you can walk the grounds on, although most are private and only have a few days open to the public.
This is a super nice place for a high end romantic dinner.
http://www.bernard-loiseau.com/ and there is a hotel there too. If you join Club 5C (free for Amex Centurion) you get a nice upgrade and other bennies. The town is very special and there are several castles nearby as well as a huge national park.