I (18m) have been dating my girlfriend (17) for close to a year and a half now and we have an amazing relationship. There's its ups and downs but generally we're still stupidly in love and we plan to stay together all through our respective college years and eventually live together. 

However, she has told me multiple times that friendships are more important than relationships and she prioritizes her best friend a lot to the point where I'm not first in her life, her reasoning being that friendships last longer than relationships and it's best to give your friends more. 

I disagree quite a bit with this since all of my friends don't make me a priority or make me feel wanted like she does, and all of my close friends have found people they like more. I've been giving her all of my attention and even though we argue sometimes (mostly my fault since I have a tendency to be miserable or careless) I've changed myself so much for her sake and I've always been there when she's needed someone. I can honestly say she's by far my highest priority and I do everything for her that she needs even though she's very independent. 

Right now, her best friend is talking to one of our mutual friends and my girlfriend is upset that her best friend isn't giving her a ton of attention and I got in a kind of bad mood after we talked about it and assured that she's being reasonable and there's no issues with their relationship. I told her it upsets me that she puts her friends above me when I believe I've proven that I'm always there for her and her worries are unfounded. She told me she still disagrees and she thinks giving me more would push her friend away, who has been getting upset herself when my girlfriend gives me more attention. 

I thought that the situation would show that I'm worth more than being second best but she's even more upset and has gone out with her friend right now so I can't talk to her for a little while. 

AITA for wishing she'd put me first?