Without you in my arms, I feel an emptiness in my soul. I find myself searching the crowds for your face - I know it's an impossibility, but I cannot help myself.

This quote is expressing how the speaker misses the person they are in a relationship with. The speaker is expressing a deep emptiness without the presence of their significant other. Even when the speaker is out in public, they cannot help but search through crowds for the face of their partner, even though they are aware that this is an impossible task.