Oh now that I hear you! It started when I was in my early 20's - ever since then - if it spins, I skip it. Just can't do it. Hate it. Makes my stomach churn. I did a Tilt A Whirl ten years ago and I thought I was gonna die. I went to a regional park awhile back with my friends and they laughed at me because I won't do a lot of the "kiddie" rides because of it but I'll jump on anything big. They all get squeamish about water rides with drops, etc. - but I love them. Even one as steep as Jurassic Park - all over that, love it. But as you said - teacups? I don't think so haha.
(When I went to Disneyland, I just had to do Roger Rabbit as a massive dark ride fan, and thank goodness I was riding with a massage therapist who has extremely strong arm muscles so we could keep it from spinning so I could actually enjoy it haha.)
But roller coasters, most thrill rides - do nothing like that to me. But stick me on a carnie ride, and I'm done for! Interestingly, M:S doesn't really bother me though. Something about Everest, though...my niece loves it, and because of her complications in loading on the ride they have often allowed us to stay on multiple times (it saves everyone time, because it takes us a good couple of minutes to get her on and then off) I've done it twice in a row before - and I will for her - but if I went a third time, I'd be down for an hour after, LOL.