APATHY: Lack of interest or concern, especially regarding matters of general importance or appeal; indifference. Lack of emotion or feeling; impassiveness
well firstly, does she know you have feelings for her? if not then tell her. and even if you think she does, tell her again. if she does know for sure, try talking to her about the situation. this...
well...... look for another girl that likes you if they don't ....then just stay single . or maybe she'll take u and you'll be happy if she does not then sorry buddy