How to end a bad friendship?

She's the type of person who will absolutely BLOW UP on you when things don't go right. She's completely two faced and feeds off of high school drama (which may be somewhat "normal" except we are in COLLEGE- she's still stuck in high school while everyone else has long moved on). I'm trying my hardest to distance myself from her and I haven't responded to any of her texts or calls since I've been home for summer term. It would be easier to cut her off except for the fact that my other friends still keep in contact with her and I'm afraid a whole scene will break out if I confront her directly. She's just extra baggage in my life and is not a nice person. I feel bad about this but I have long moved on from her negativity :(