When did you cry?

[the phantom]

How has no one mentioned the Rohirrim riding to Gondor's rescue?

From Gandalf's POV-

'Old fool!' he said. 'Old fool! This is my hour. Do you not know Death when you see it? Die now and curse in vain!' And with that he lifted high his sword and flames ran down the blade.

Gandalf did not move. And in that very moment, away behind in some courtyard of the City, a cock crowed. Shrill and clear he crowed, recking nothing of wizardry or war, welcoming only the morning that in they sky far above the shadows of death was coming with the dawn.
And as if in answer there came from far away another note. Horns, horns, horns. In dark Mindolluin's side they dimly echoed. Great horns of the North wildly blowing. Rohan had come at last.

From Merry's POV-

And straightway all the horns in the host were lifted up in music, and the blowing of the horns of Rohan in that hour was like a storm upon the plain and a thunder in the mountains.
Ride now, ride now! Ride to Gondor!

From Pippin's POV-

But Pippin rose to his feet, as if a great weight had been lifted from him; and he stood listening to the horns, and it seemed to him that they would break his heart with joy. And never in after years could he hear a horn blown in the distance without tears starting in his eyes.