Elena! Like He cared and loved them but in different ways. Plus resisted compulsion from Klaus an Original when he told Stefan to feed on Elena. Klaus said and I quote “The only thing stronger than your craving for blood is your love for this girl” Plus Stefan stabbed himself with a broom 🧹because he didn’t want to feed on Elena

He gave up his life to save her daughters who weren't even his, he stayed with her even after realizing the children weren't his, he fell in love with his best friend. I'm pretty sure he loved Caroline more.