Dining Out on a Restricted Diet

Without going into detail, I learned recently that I need to eliminate several foods from my diet. If I cheat, or eat one of these things by mistake, I will suffer physical discomfort.
This is what folks with allergies, Celiac Disease, and lactose intolerance (among other afflictions) face every day.

We make adjustments, and we carry on.

One of the adjustments I've had to make, personally, has been eating out less. No longer can I depend on the quick drive-thru option when I'm too busy to pack a lunch. Sure, several restaurants will make concessions for special dietary needs if you ask. But are you sure those fries you love are "just" potatoes? Is the burger patty "just" beef?

I scoured one or two fast food ingredient websites and found out one restaurant's hamburger patty is 100% beef with no fillers (yay!), but the same restaurant's Angus burger has lots of things mixed in the beef (yikes!). Unaware folks on a restricted diet might think they're okay requesting no condiments or removing the bun, but they'll get nailed by the special flavoring in the meat itself and never know why they felt lousy afterwards.
I was very sad to find out my favorite fast food fries (which I had thought, "It's just potatoes, right?") contained milk and beef flavoring. No wonder I loved them so much. They fry the equivelent of gravy right into the tasty fries!

Ordering a meal at a restaurant starts to sound something like Meg Ryan ordering a salad in the movie "When Harry Met Sally".

So, I am very appreciative of restaurants and waitstaff who are patient and understanding of my multiple requests. (It could be they are more used to patrons asking for special dishes than I am used to asking at this point.)
I've found three Janesville dining establishments so far that have been very accommodating. (I'd probably have found more if I ate out as much as I used to.)
The Riverside Restaurant and The Pitstop BBQ are downtown Janesville and within walking distance of the WCLO studios. Granted, they kinda know me at these places because I've eaten there before... and a LOT... but the care both waitstaff and cooks take to prepare something I can enjoy is impressive.
I was delighted to find, at a recent comedy night, that The Armory can serve me "an all beef patty, not fried in butter, no bun". The waitress took the time to parrot my order back to me as she set it in front of me. It was much more delicious than the package of nuts I had taken along "just in case".
There are probably plenty of other restaurants just as accommodating; I just haven't found them all yet.

If you have special dietary needs, how do you deal with eating out? Do you simply avoid it? Are there particular restaurants you prefer because they cater to your requirements? Please, give them credit in the comments.
Also, what adjustments will you have to make during the holidays when you visit friends and relatives for Thanksgiving and Christmas dinner?