I hear you, trust me, I've been there!! The truth is though, that we CHOOSE to invest our time , attention , energy into someone. Another person doesn't really owe us anything - unless you guys discussed things and decided to commit to each other. From your post it sounds like the girl never told you she was in love or wanted a romatic relationship. Forgive me if I misinterpret this. But sounds like you were falling in love, doing a lot of things for her but never actually talked to her about what she wants (from you or with you) or how she sees your connection. It feels really nice to be loved and cared for; I wouldn't blame the girl for enjoying your attention. I'd suggest to empower yourself by owning your feelings towards her, taking pride in being a caring person that you are and finding someone who will appreciate it <3