I have depression and right now I am going through a rough patch. I have had this for a long time and know how to deal with it and that it will go away. But of course during that time I am a bit more reserved and quite and generally just want to be left alone. But my friends notice this and become worried or interested. I definitely DO NOT want them to know I have depression (it would make things really awkward - and please lets just leave it at that). How can I reassure them that nothing is wrong and I just want to be left alone?