I think depression has guilt as a younger sister.....

I understand...Probably every one of us has had some interpretation of what you wrote happen to us.

People are compassionate and try to help...which is truly good of them. But, and this is my opinion only, people think that if they "help" you through it, then you will show some improvement.....but depression doesn't work that way. Then I think that they feel as if they tried their best but you're not responding (of course, you can't) then they feel a little bad about that and tend to withdraw.....

It's not personal and you shouldn't feel that you did anything "wrong". You are simply, temporarily, a slightly different person than you were before.

That's why depression is so isolating. Unless your friend has experienced it, she has no idea. And she might not know how to proceed.

I suggest that you email and try to explain that it's not as if you can control what's happening to you. You appreciate her support and it doesn't go unnoticed. And tell her that her just thinking of you and saying hi to you means the world.

TBH and you won't like this....but some friends can't handle this. It's not their fault and it's not your fault.