Thanks, MM.
I think you may find (she says cynically) that losing friends is a natural part of life with a chronic illness, and you may well experience more loss in the future. People like to think that you're going to get better. They're more used to things like appendicitis, where they can make a big, supportive fuss, there is an operation, and the person gets conveniently better.
You upset their world view, MM, and show that illness can happen to anybody. Also, a lot of people get frightened at the thought that you may stay sick, and may need their help, or, at the very least, be a bit less fun to be around, so they fall away.
You may well find, like many of us here, that many of your "friends" start to blame you for not getting better - you're not trying hard enough, not eating the right foods, whatever.
I'm not sure why I'm telling you all this, except to say that it isn't your fault that they have fallen away, and will not be your fault if it continues to happen. Most of us have gone through the loss of good friends, though some of us have been lucky enough to find even better friends in the process.
Ivy.