Nice tones but focus seems a tad TOO soft and her right eye (your left) seems overly mucked with in the post processing department. I would crop about an eighth off the right hand side to make this shot more dynamic ... "Rule of Thirds" again ... 7
I like the left half of the face, i don't like the right half of the face. Very nice light and very clear eye on the left. The right has the shadow side, but while a slight turn of the head (look at the slight light fall just above the eye) would have resulted in a clearly visible eye as well, now it is hidden and very hard to see because it is in the darkest part. On the contrary i do like the light falling on the hair (both sides).. it is not overexposed which is very nicely handled.
Position-wise: i like it.. it works with her. Very nicely captured. But i would have asked her to turn her head just a small bit.
Expression doesn't bring me the message 'heart' but more a questioning look.. again it fits with the dark-light part because a question could turn either way.