Frenemies and the "me friends"

Lets face it, everyone has them. Mine comes in the form of a 5'1 bitch named emily. How fitting, it sounds just like enemy.  I'm not a "snarky" person and I'm never looking for a fight.  So people who are baffle me.  Especially when those people pretend to be my friend.  I don,t think friendship looks like blaming someone or calling them out on all their faults, I believe it's loving them past the mistakes they've made or possible character flaws they incur along the way.  So, i have been trying to do just that. Let me first tell you that it has been to no avail.  She laps up the attention sure enough, but whenever something doesn't please her she lashes out at the people around her.  I have had the misfortune of being one of those people on more than one occasion.  From prospective boyfriends, to snacks I'm eating this little whirl wind can find fault with me.  Other friends/confidants have suggested jealous as a motive, but come on does jealous have no end?  I  definitely see no end in sight. UGH! These are the friends that you feel as though you are walking on egg shells during simple day to day interactions.  Let me tell you THERE IS NO WAY TO REMEMDY THESE PEOPLE!!! I've tried ignoring her, she fires back with facebook messages ( how lame i know, its like competing in the special olympics, even if you win your still dumb--okay that wasn't nice or politically correct, but you know what I'm getting at).  I've also tried a more hands on approach of fighting back (nothing physical) verbally of course, also to no avail...she has no legitimate arguments...they are so circular, you can't compare apples to oranges. My last attempt at solution has worked somewhat better, acting as if nothing is wrong.  By letting her work out her personal issues in a matter of oh a half hour, she acts as if nothing ever happened. Yes, i think this bitch is bipolar.  I'm deeply sorry for any of you who also have an EeNmEiMlYy in your life.