It’s quite common, to get carsick when someone else drives but not when you do.
My sister in law gets carsick real easy unless she’s driving or the driver is someone she trusts; if the driver is someone she trusts she can fall asleep in a fifteen minute trip.
People in my family only get carsick very rarely, it takes an amazingly bad road or driver (the last time I got carsick, we were told that the dirt road we’d been on had been closed about half an hour after we got on it); my middle brother used to throw up in every car trip but that got solved when he finally managed to return to sender that Lego piece which had been bothering him (my parents refused to believe he’d swallowed it - for over ten years).
My mom used to be as bad as I am, but she “outgrew” it in her late teens/early 20s. I’m 41 and still waiting. My dad and my brother have never had problems with it.
I went for a pedicure the other day and they had those awesome (according to my best friend) massaging chairs. Um, yeah, I had to turn it off after about 30 seconds or else I would have been running barefoot to the nearest bathroom.
I get it, and my grandmother did. She had it to the extent that movies would bother her. I need actual motion to get sick.
Mine has gotten better- it was terrible when I was a child, isn’t usually so bad now. But I try not to sit near the back of buses or read in the car. I used to be able to ride amusement-park rides, haven’t tried that in the last ten years though. I can ride in the back seat of a car without getting sick; my grandmother couldn’t do that.
We took long car trips when I was a kid. If there is a personal hell for me, it certainly includes a long period of time being forced to sit still and not being able to read. I won’t drive anywhere further than about 3.5 hours now- if it would take longer than that to drive, I fly. If I have to sit in a small seat where I might get motion-sick for 14 hours, I want to be in someplace cool like Australia at the end of that, not just Florida. I find driving tiring and get really tired if I try to drive for more than about 3.5 hours (if it’s at the end of a work day, dangerously so), so that’s out, too. No long car trips for me any more.
I find that it makes a difference if there is air flow. My motion sickness is much worse in a car with the air vents off and the windows rolled up. I think this is because moving air is another cue that says “you’re moving” to match what you’re seeing. The first thing I will do when I sit down in a car or plane is turn on my air vent (or ask the driver to turn on some air for me). The air vents in my car are on at all times when I am driving. I adjust the temperature as needed, but I never turn them off.