I am a 23 year old man and my sister is a 20 year old woman suffering from severe OCD: she is unable to process information efficiently, has compulsive movements, sometimes struggles to formulate sentences, needs help eating and getting dressed, suffers physical pain, plus other hindrances on her daily life. She is on medication and sees a number of professionals from the NHS. The issue is that her OCD is getting worse despite the help she is receiving. In fact there has been a dramatic decline in her condition in the past 6 weeks, such that she is now fully reliant on my parents to help her through day to day life. Whereas before she was able to operate well in certain situations, such as work (she works for a catering company), people now are starting to pull her up and ask what is wrong, even in her workplace, as they can notice her in distress.
As a result of her worsening condition, she is not practicing what her therapist and physiologist are advising in order to manage her OCD. Due to confidentiality and my sister's refusal to grant consent to my parents to be involved with the therapist/psychologist, no progress is being made and my parents are left in the dark with regards to what is needed to help my sister.
What advice can people give me on how to tackle this issue? How can my parents become more involved in helping my sister in tandem with the professional help she receives?
Any help is really appreciated!