Is it my thing or actually you can't increase Alexandra love? Every time I look at it I can see everyones loves except her's, she just appears in gray, is it because it hasn't yet been implemented or because a choice I made in the game?
When a girl is greyed, this means you failed (or willingly choose to close) her path. Alexandra is probably the toughest, as a first bad impression is enough to stop it all. You should start again trying some other options with her ;-)