Eating out when you are on GF diet is a challenge but while visiting NYC for a few months I have been able to explore some really amazing restaurants in Hell's Kitchen.
For example Bar Bacon on 9th Avenue between 54th and 55th street. Most of the items on the menu can be made gluten free and the dash of bacon on the meal made it extra yummy. You can order any burger or salad and make it gluten free. They have gluten free buns available and the meat patty is fresh and juicy. The down side is you can't have any of the sides because they are all covered in flour before being deeped fried. On the other hand the ambiance and service of the the place is fun, loud and entertaining. We had a great time!
If your looking for a more quiet romantic setting I suggest Bocca di Bacco it is next door to Bar Bacon on 9th Ave. They have gluten free pasta available with any sauce on the menu. It was more expensive than any other pasta meal I've had in the city but it was delicious. The service was good and very considerate of my GF diet. It is a good place to go on a date night.
I just love a eating out in NYC Hell's Kitchen!