actually i think that both MiSato and Mei are in love with each other. But only Mei has confessed his love (read The Prequel) and he's still Waiting for Misato to understand and trust him completely. Misato, instead, is trying to hide his love for Mei because he thinks that Mei is still in love with The other sato (twin older brother)
Hope this helped you to understand more :)
ah~ that makes more sense. but i don't think Mei ever confessed his love to misato? i think like Misato, Mei has kept quite about his love for him, because he thinks Misato still thinks, that he is in love with the twin brother Satoshi.
So is he not in love with him or is he in love with him?