I would stay as far away as possible from this person. I would suggest putting her contact notification alerts on 'silent' so she can't just randomly affect your zen until you are in the right frame of mind to take a look at her negative texts. If she emails you at all, mark her as 'junk' and (on liz's suggestion) rename her 'enabler' or 'junk' or some goofy name that would make you chuckle. If she leaves voicemails, let your mailbox fill up so you don't have to hear her voice. Or just block her from contacting you.