I get why tho.
I'm partially normal, so I know why they do this. Same reason, if you see a stranger approach you and they look normal so you give them a benefiit of doubt they have a legit question, maybe like "you know where xyz road is??".. but, they begin saying "I need a bus ride, and... "
BOOM. You know where this is going. You instantly, become exacactly the way you are describing they do upon saying anxiety. They "lose you" at that point.
But, think of why. With the stranger on street, it's cause we had high hopes for them. We hoped they were a lost traveler, asking for directions. To discover they are in fact, "damaged", and seeking "money or change", was disappointing.
The people, who talked to you, were HOPING you were like them: normal. (Normal people have anxiety too, but don't talk about it. Like not talking about needing air, or oxygen)
Upon hearing that word, they "lost you" then. Because, that word, tells us this person is going to be that "needy friend, insecure". Not that friend to go out meet chicks post up on FB etc....
Everyone secretly is looking for that "cool friend who can raise them up socially"
To hear "anxiety", uh oh. This person might not be cool......
You know what I mean?