Responding to a criticism

I've heard the movie criticized on the grounds that there are no scenes at the field hospital showing Zhivago and Lara falling in love.

Response: From the standpoint of the married Zhivago it was love-at-first-sight (or, better described, totally-intrigued-at-first-sight) when he first sees Lara at the apartment wherein her mother tried to commit suicide. Yuri has the same "Whoa Mama" response when he subsequently sees her shoot Komarovsky at the party. Even their initial non-meeting in the streetcar where they merely brush shoulders the camera immediately cuts to a shot of the roof of the trolley where there are literal sparks flying from the electric line (!).

When they finally meet-up at the field hospital several years later Zhivago falls in love with Lara during the six months working together and 'fesses-up at the end. It's clear that Lara pretty much feels the same way, but she nobly encourages him not to do anything that would make it necessary to lie to his wife, Tonya. This shows that there were no hot romantic scenes up to this point in the story. Nada. The two were simply working together in a mundane war situation where they developed unspoken feelings for each other over the course of the six months.

This was all the prelude to the third act where they happen upon each other at the town in the Urals and proceed to have a steamy affair. As far as I'm concerned, there's enough romantic drama in the third act. Their encounters before that were just preparatory stepping stones to their forthcoming intimate relationship.