Nato shoots down Germanwings Flight 9525, page-25

Its not impossible that the aircraft was shot down by the military and it most definitely would not be the first aircraft to be shot down.
There have been numerous shoot downs by various countries of civilian aircraft and then some have been denied for years.
So it is not impossible, however it is very unlikely in my opinion, but there is always the chance especially given the lack of real evidence and the convenience of the circumstantial evidence, the lack of the data logger so there is no evidence about the control settings of the aircraft. Lots of people suffer from depression and go on to lead normal lives in all walks of employment including doctors, and all manner of professional people as well as soldiers, sailors, airmen and politicians who run countries.

Just saying it is possible. They tried to demonise the pilot of the Malaysian aircraft that went missing over the China sea by insinuating there was some problem with the man because he had his own simulator.