The war was simply too costly. France had an enormous supply of manpower and the economy to continue fighting, whereas England lacked the ability to continue to field an army capable of maintaining their victories. Furthermore, Parliament was unwilling to continue to raise the revenue necessary to maintain the army in France. The nobles in England also lost their land holdings in continental Europe, which significantly discontented the noble class.
Keeping this light, the English were unable to keep their armies funded and reinforced. The noble class in Parliament simply did not have the political will to continue a dynastic war.