I'm sorry, it's SO hard when a spouse doesn't understand. Mine doesn't most of the time.
I also deal with sensory overload but I'm lucky that I just go into a mental shut down (I guess that's the best way to describe it).

Maybe try to sit down with your DH when it's a clam time and try to explain what your going thru and see if you two can agree ahead of time what you can do if anxiety gets bad, like using ear plugs if it's the noise that gets you or if it's the over all crowd getting a table where you can't see all the people.

We like to take our kids to the zoo a lot and I go into a mental shut down most of the time but it's OK, DH helps keep the kids close by and clam and I get to push the stroller (it helps me with walking, LOL, none of the kids ride in it much any more so it's starting to look odd ). Anyway my point, DH knows what "can" happen with me and we are able to go and have a nice time with the kids and he knows how to help me get thru it with out us fighting.