It's not because I have strong feelings about the products or the company, or just that I dislike shopping. There aren't any other stores that create the same reaction. Stores filled with products I hate, stores filled with products I love, stores filled with temptations, big stores, little stores, ugly stores, beautiful stores, malls, they're just places to shop, and while they might make me feel bored or irritated after a while, I don't get nauseous. They don't fill me with dread.
I honestly don't know why IKEA stores affect me like that. At first I thought it was anxiety about being disoriented, but it happens to me even in the local store where I know the layout. I have a lot of faith in habituation, mindfulness, and thinking things through as ways of mitigating anxiety, but they haven't helped. The only thing that affects me as viscerally and predictably is my fear of heights, so whatever it is, it feels primal.