Disturbed mind. Do , i m very helpless.

Hi , I have one elder sister .she is 29 years old, she is deaf and dumb . she puts hearing aid  too . she did schooling till 12th ., And after that she started at home . from last 2 to 3 mnths we are seeing too many changes in her . she thinks too much on small things and get tensed . she gets  sleep very late night ( she was very punctual on her routine ) . she gets angry soon , she doesn't share what she is thinking . sometimes she is like she wants to marry sometimes she tells no , we actually belong from small city , ahe doesn't wants to get married in tha city , she has desire of getting married in big metro cities but we can't bhi initial stage it's very compulsory that she needs to stay with my parents for support as she is very innocent . I am very worried about what has happened to her.  when we talk she will get angry and ask us to be quiet . I try to talk to her but she will never express.  can u pls help me what to do , I m very helpless .