Manic depression and clinical, or "regular" depression are not the same thing.

A person suffering from manic depression is prone to bouts of extreme depression alternating with bouts of extreme "high" - that's the manic bit. The up part of manic depression can be worse than the down part - I've heard of people who burnt their house down because they thought the flames were beautiful, people who took all their clothes off and went ou worshipping nature in sub zero temperatures... Basically if someone does suffer from manic depression they are extremely unlikely to be just drama queens.

Clinical depression, on the other hand, is indeed something of a hobbyhorse for people who don't want to deal with their problems these days. Still, when genuine, it can be awful. And the enthusiasm with which doctors sedate their patients with Prozac and other such drugs instead of recommending therapy is disheartening indeed.