The hardest love of all, is that unrequited. You obviously care very deeply for this girl and that's nice, but she said it herself "you need to know your boundaries". It's very very hard loving someone and then having to see them share their life with someone who isn't you, but if she doesn't feel the same way about you then you can't blame her for that, its not something that she can learn or something that she can force. She either likes you, or she doesn't. And its pretty clear she doesn't. The sooner you accept this, the better its going to be for you.
I don't know the exact situation, but if you've done the grand gesture of giving her your jersey then I'd say you've crossed a line. I know you've been her friend a long time, but imagine how her boyfriend felt (or he would have felt if he saw). How would you feel? You probably made her feel really awkward. She doesn't mean to hurt you and she doesn't mean to treat you this way, but you're not leaving her a lot of choice when you put her in situations like that.
It seems to even of got to point where she no longer feels comfortable just being your friend and talking to you about personal things. You've made that awkward for her and in you attempting to get closer to her, you've actually started to push her away. I understand that she might have 'lead you on' a bit, by not making it clear in the beginning that she wasn't interested, but it seems to have gone a bit too far.
Whats your relationship like with the boyfriend?
There is a way that this can be fixed. Starting with you attempting to get over her. I know it will be incredibly hard, but its something that you need to try really hard to do if you have any hope of saving your friendship. You need to show her that you can still be her friend without being slightly overbearing and making her feel uncomfortable. Only then will she start to open up and come back to you.
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Week in and week out,
Your lucky charms will always let you down,
Maybe next week we'll see,
Maybe