Actually, YES, it is normal to feel Blue or depressed when you are sick with the flu or a bug!! There are a few reasons why too. First you are not getting the same amount of resoritive sleep you nomrally do. Most likely you are trying to rest more but your body is working hard to "fight" the illness and not to rebuild what it is loosing. Your body must maintaint a certain amount of seritonin and other neurotransmitters in order to "feel" well and happy. We can NOT do this if we do not get enough rest or do not feel well. If the body is under any type of "physical" stress, we loose and do not maintain enough neurotransmitters. Physical stress can be anything from falling to throwing up to a really bad headache. Even certain exercises put physcial stress on the body. The challenge is determining what is normal and what is a problem. If you feel bad, blue or depressed for a long period of time AFTER the flu has gone away than I would speak to a doctor. There certainly are plenty of meds out there than can help you jump start your system again! None need be forever and they get better all the time!! Perhaps you just need a little to help you get going...that is OK!!! Some other doctors may suggest something like biofeedback as a means to help you work through it. That may help also! Perhaps a little massage therapy... couldn't we all use a bit of that?? What ever helps you feel better and gets you back on you feet! Your deffinately NOT alone!!!!