My sister is very unhealthy, Piscean soul.
Her past life I am sure she rotted away in a hospital somewhere, judging by her behaviour now and certain astrological placements.
First of all, this is very sad hearing how the enemy works, bringing to difficult lives for wonderful people ad souls like probably is your sister. Does she know you are a Zevist or you are talking about her situation on some random forums, etc.? As dumb as it may sound, tell her some people like us here do care about her situation, like for example I do now - I feel empathic with this kind of suffering as it's part of my existence and others' lives connected to me, since barely my whole life. I am just taking some minutes in my life to care about her, exclusively for her, so let her know. People like her who I met in life were heavily neglecting themselves, for lack of self-worth feeling. Knowing some random people found her worth of a few words and time, may have some unexpected good effects on her overall ratio of supporting her life.
I am not advanced enough to post more spiritual advice, than the good ones already posted by others on here. I have a very practical "hands at work" approach to problems, in addition to meditation and magick, so I want to add some tips to support the spiritual efforts - all of this comes from years of experience with people.
Words.
Mistreated people by the enemy suffered for sure heavy emotional violence, through words and behavior. It is said in communication words count less than 10%, while non-verbal communication (attitude, tone, hand gestures, moods) are the remaining 90%. I mean, problems do not come only from curses, but on Soul's damage in itself. So having a very warm and kind way of relating to her, with the right tone, may slowly help healing her from the inside. Your *will* about a kind communication may put energies in her throat and other chakras for the good. Most damaged people I have seen, have hard Saturn aspects to their Mercury/communication areas and receive harsh verbal treatment also in this life - as a result of past karma. They project this in their aura so they also receive mistreatment from other people, who sense this, also they are prone to attract it. Working actively against this, weakens this karma.
If she was rotting in a hospital, hunted by the enemy or christian nuns, etc. she may have experienced lack of food, malnutrition, forced feeding with rotten food, etc. So this is probably why her unconscious mind is trained to refuse food. The key point here, is "recreating" past life (or childhood, in case of abuse in thus life) conditions, so that her unconscious builds a bridge between past and present way she receives care, now from you. The traumatized and damaged unconscious may have no clue of time, so giving her good care now may in a way "correct" the past shit she had to endure, like if she is still there.
My GD was paramount in guiding me through this process, as He managed to recreate subliminal ties to past issues, as I explained.
There are may other details, but at the end, treating her physically and verbally with a lot of care, is of much more help than we may think.
People who suffered this way may have some emotional "selves" stored into the mind, with a partially independent consciousness. If they sense they are treated with much care, they may strongly react and boost the overall mood to very high levels. A pwrson with a high mood, will be prone to help herself more. It is important to keep this going, or the mood may fall down quilcky, leadind to neglecting self-care again. Those kind of people may be very emotionally delicate and rapidly swinging.
I hope this may help here.