It means that you are a typical female living in a dog eat dog world. Its pretty normal for even the Best of Friends to feel jealous or hate each other sometimes. ITS QUITE NORMAL.
But... this is where years of understanding comes out to play, friends are hard to get nowadays, Best buddies are rare if you only consider those who are willing to sacrifice and share stuff with each other.
I think the feeling you felt now is just temporary, its hard for you to accept that those attention that you had was suddenly divert to your best buddie.
Advice for You--- Accept that your friend is beautiful But so are you...
The truth is every person is like a diamond, you just have to discover it!
Gd Luck and hope you get over it soon....
