I guess I took her words too literally, but I had to finally be honest with her. I'm glad I did because she's now saying that it's not that she doesn't believe me, but she said that misdiagnosis can happen. Although she doesn't believe her friend has ADD because he is smart. I know plenty of smart people with ADD, I even think I may have it.
Anyway, good news is that our friendship isn't over.
I've also got a friend that suspects he has AS, and he is a good person to talk to about it.