HELP...Should i be jealous over this!!!!HELP?

ok I'm an 18 year old girl and im in love with My BEST friend(Meghan) and she had a boyfriend (Brett) and well me and her have this UNBREAKABLE bond we are there for eachother we love eachother...She knows how i feel about her how i'm In love with her..Well I get EXTRALMY JEALOUS over her and Brett and if she really loved me the way i love her she would break up with him right??? i just don't know I'm so CONFUSED..HELP PLZ