I know it sucks to realize but especially in that age (I am 19 and dating since 15) girls tend to not love you in particular but really like the feelings you case them to experience. But especially in this age this new feeling of being in love with someone goes away pretty fast. The advice I have for you may suck to hear and is a bit manipulative but the only thing that worked out for me when dealing with girls under 18 years... Show her that you also have options and that she is not the only and last girl you will ever love/do/like/whatever. But you have to show it by your behavior not with your wordings. Don't actually say to her "wow I know this girl which really wants to be with me so.. If you break up I can do her". But rather do something with your female other friends regularly. At best you have one female friends and you hang out with her... Or you just mention only her when you and a group of friends do something together. More like when she asks you what you do Saturday night you answer "Oh Jessica invited me for a movies night at home. I guess some other friends will be coming too. I am looking forward because she is really nice currently". In the "professional dating scene" this is called dread game. You play with her fear of loosing you, which causes her to invest more into your relationship. And investment from her side is always a sign for attraction. Young girls need the control about their relationships, because they often make their self value(dunno if that word exist in English.. I am German) depending on how good they are at receiving everything they want in relationships. And by taking away the power to end it.. Or at least by making her think you are also able to end it if she isn't "enough" She will automatically try to take this control back to her.