When talking about the likely cause of migranes, keep in mind that they can be triggered by a multitude of things.
I, for example, suffer from Stress, sensory, and dietary migranes. Some people are lucky enough to only have one of those as triggers, and some people are unlucky enough to have all of them. In the case of stress, and stress alone, which is probably the most frequent cause of migranes. Removing a primary factor of stress can completely relieve the symptoms for quite some time, or even for good.
While I wish it was that easy for me, I have found my migranes are triggered from stress, eating habbits or changes in eating, and sensory (i.e. natural light). So the only way for me to be migrane free, would be to live a completely peaceful life, eating a very bland diet, and never ever step foot outside during daytime.... And now back to my job in the army instead of posting comments....