I'm guessing it wasn't so much the traveling as it was the poor communication. I know couples where one likes to travel and the other one doesn't, but they communicate with each other and find ways to make it work. Sometimes they'll travel together, and when they do they make sure they prepare for their differences in needs; sometimes one will travel instead with maybe a friend or in a group while the other doesn't, and they're both okay with it -- but bottom line, they don't act out or shut down.

I know for myself, a close friend and I are planning a trip together next year and we both have very different needs, and I've said to him, "we really have to talk about this, because I'm concerned about any conflicts that may come up," and he agreed. I've tended to think of myself as a pretty good traveler so far, but we all have our stressors, and lately these days with my mobility issues it's an extra sensitive subject.

I just finished a 3 day road trip from New York to Montana. My daughter has mentioned a couple times the differences in traveling with her mother and me - she feels less like she has to be an adult with me around.
She does get a bit nervous about perceived burning smells from the engine compartment- just like her mom.
Definitely no shutdowns or tantrums

It sounds like you and your ex wife were not compatible, at least in the respect of the enjoyment of travelling. As she’s now your ex...I presume it wasn’t the only thing you were incompatible at. If travel is to be enjoyed in partnership, there has to be a basic agreement between you in the first place, regarding the itinerary. As you point out many things can go wrong or cause stress whilst travelling, some people are just bad travellers, so finding that out prior to embarking on any trip would be helpful. You can’t just wave a magic wand and make stressed out people less stressed, but you can show understanding, and not show irritation if they are not as blasé about travelling as you are. Travel and motion pills (sedation) are often the only answer for some who get stressed or sick when travelling. Hope you find a more compatible travel companion in the future.

If you're the one dragging her to places she obviously doesn't want to go why should she be the one to apologize? Why aren't you apologizing for putting her into stressful situations, evidently time and time again?