Cdunbar
For a beautiful and romantic area for an inland honeymoon look into the Mt. Pine Ridge area. Absolutely incredible.
This area will also allow for relaxation as well as spectacular adventure. You should hike the ATM caves from that area if you enjoy being active and adventure, probably one of the most exciting tours in Belize.
Here are a few locations in the Mt. Pine Ridge Reserve highly recommended for a romantic getaway
http://www.fivesisterslodge.com/ Backs right up to the waterfalls!
http://www.blancaneaux.com/ Incredible accommodations (a little pricer) If you stay in the Mt. Pine area at least eat at their fabulous restaurant!!