First off, I have to say that the worst thing she can do is not to tell you to go away, because you're so smitten by her that it will probably crush you. You don't want to hear that, because if you did, you would have also moved on and stopped thinking about her. Anybody can sense that. I'd be willing to bet that she is trying to find a way to not only let you go, but do it so that she doesn't hurt you. That's the reason for the "call me" at the end of the note, just to try to stay away from any conflict.
One thing I've realized is that women are hardly direct in what they say. They always try to be friends with everyone and make as few enemies as possible. They don't enjoy conflict either. It's probably one of the top things on their list, which is why they take things slower than men. If they feel that there is a possibility that they're going to get hurt or hurt someone else, they'd rather cushion the fall before it happens, sort of a precautionary measure/defense mechanism.
This gal that I'm talking about has all sorts of stuff going on, and to me, I see them as largely an excuse, but of course you have to judge it based on what you know about the girl. Is she very independent? Is she very needy? Is she a player? If she's needy, for example, she will be the type that will try to let you off easy because she probably identifies with the pain of liking someone and not having them reciprocate, whereas if she's the type that is very independent, then she will probably be more straightforward with you.
Haven't you ever noticed that you will think for other people, and when you do, you use your own reasoning more likely than you would use theirs? Heck, you even did it here, when you assumed that she would just tell you to get lost if you gave her the flowers. I'd have to think that you know her pretty well to be able to assume she would do that. Girls act in unpredictable ways, and unless you knew this girl for all your life, you probably can't say what she would or wouldn't do. Being that things didn't go bad, she probably wants to find some way to keep you as a friend rather than lose you. Girls can do that more readily than guys.
A girl's social circle is important for her. Think about it, even when we were in elementary school, junior high, or high school. In P.E., if we were choosing for sports, girls chose the teams based on their friends. Guys chose them based on the best players even if it wasn't their friends. This means that a girl places a high value on friendship, maybe even more so than a relationship, compared to a guy. Problem is that she doesn't want to breach that friendship while the guy may want to, which I guess makes sense if you consider that the guy doesn't care if the girl is his friend, if she's the best match for him, then he wants her on his "team" so to speak.
Anyways, that's how the dynamic works. You don't have to like it, but you'll have to realize that that may be what's happening. So like I said before, the closest relationship you can probably have with this girl for now is a platonic friendship. It may end up being more a long ways down the line, but don't sit there waiting for it to happen, that's for sure.
