i'm not too sure about this, i don't think he really loved kay in the highest sense of the word, i mean hadn't he been back in the country for a year before he bothered finding her? and he got married to someone else when he was moved out of the country, not exactly the signs of someone deeply in love. i would add however that when said...

"his eagerness to have children was the underlying factor in his choice to marry her. Not one primarily out of love, which was the reason he married Apollonia."

at the time he seems to decide to marry Appollonia 'lose a father instead of....'
he hadn't actually even heard her say a word? whether he could have fallen in love with her just from seeing her walking in the field with those girls is a whole different question...