[Sombre]

Basically you had a bad position and I think you made it worse by spreading yourself too thin. You need to concentrate on the core provinces while sending out smaller armies to raid the enemy, moving around in their territory grabbing a province, setting 200% tax and hopping on to the next. Don't chase the AI, make them chase you while your armies and larger PD protect the more important inner provinces. Once war starts you can afford to lose the outside ones, provided you are taking 1 or 2 a turn from any attacking AI and taxing them 200%.