1) The brother did like her, but not in the romantic, I love you, marry me kind of way, but in the
Ted Bundy, I set and watch you, lust after you kind of way.
2) I think she as a certain amount of affection for William (the Dukes son) and would have married him if the whole evil queen thing didn't happen, but at the end of the movie, after she ate the apple, he kissed her and she did not wake up, but when the Huntsman kissed her she came back to life. William at the end of the movie is in the crowd and not by her side which suggest that he and she are not going to be together.
3) The Huntsman's kiss is the one that woke her. While she is dead he tells her that he is a better man because of her and in short he loves her, she is seen crying after he leaves which suggest that she heard what he said to her. Also while they are with the dwarfs they share that look and then the one dwarf ask him if what he is doing is just because of the gold or is there more, again suggesting he is already developing feelings for her.
However, at the end of the movie they do not really tell you if she is going to end up with him or if he is going to be leaving. They do, however, share a knowing look. I like to think that the huntsman goes on his own for a while to allow her to be a queen to the country and then comes back later (maybe sequel...there has been talk of a possible sequel before even the movie was released). I think that at the end of the movie the producers were trying to make her look like a strong woman who could stand on her own rather then needing a king by her side, which may be why they left the end of the movie so ambiguous.
watched the movie today