dehydration causes sever headaches, you drink and they get better. Depression can often be brought up when you are lonely or by yourself, because often times when we're alone our thoughts tend to drift towards the darker parts of our lives, our hates, fears, instabilites, etc. So, obviously being around people would alleviate the symptoms, for a short at least. Many fair skinned people have a problem with the son, the Irish are a notable example. Its true, we really don't tan well.
Always try and find a mundane reason for things happening before you look to the mystical