this is only my personal opinion, but:
for a relationship to work, you have to show understanding for your significant other (but still be the one on top of things).
consider her approach towards you--> has she ever asked you to change something about yourself or had you do something you weren't particularly in to? if so, dont you think you should be allowed to get things your way once in a while?
secondly, remember that girls and their bff's are really attached to one another, and they at times would be willing to do more for them if their "bff" was in need than if you were in need (this is not always the case but i for one have seen it done)
i think that the phone issue is easier to solve, from what i can read youre saying she seems to be more into her phone than you .. could be a sign of disinterest towards you, but then again you should make it clear that it bothers you, it wont sound like your needy if its the first time you ask her to do something for YOU.
the bff issue is a tad more complex. they can be a hassle and often times are, youre pretty much right on when u say that she's frustrated and she might be jelous not to have someone in her life (or does she?). by no means should you tell the bff to fark off, that would put your good image and reputation on the line. perhaps try and avoid situations that will force the three of you to be together, especially when you feel like spending some time alone with your girl.
its important to let ur girl know what you want, but its also important to give her some space so to not seem too needy. in the end, you are the only one to know what you can ask for and what you should keep to yourself, and if you think that she is capable of understanding that her behaviour might be irritating for you, than you should voice your irritations.