Sheila,
I had the same experience when I was diagnosed, and people I never expected to be supportive were totoally there for me, and then others dropped out of sight.
Looking back, I can really say that I was glad to figure out who was "true blue", and worth my time and friendship.
Just don't be too quick to write people off, as some just need to wrap their brains around the issue and figure out what to do or say to help.
Good luck, and of course you have a lifetime of friends here, even if they are new and only on a page.