Folks who don't have our illness have NO CLUE what we go through and cannot tell us how to "manage our illness." Even folks who do have our illness, should not attempt to do such a thing as was done to you in that note.

Therapists and our psychiatrists sometimes don't even know how to help us! How can a "friend" know more than they do?

Try to ignore it. It may have been intended to help you, but obviously it didn't, end of story!