What can be done for a person always staying in her room without any communication?

Hello doctor,

My issue or family issue is how to deal with my sister to get her out of the room and act normal again. I have been praying. I also went to a psychiatrist once but that one session is not enough to answer all my questions about my sister. She is 30 years old. She is not normal and it is breaking our hearts. She literally locks herself in the room the whole entire time, the few times she gets out (she times it while we are asleep) so I did not see her the first three days during my visit to my family. After that, I saw her when she got out to take food from the kitchen. I followed her and I greeted her and asked her to greet me back and give me hug, but she ran back to her room and locked herself. Other two times I followed her and touched her arm softly and I said "I need to tell you something dear", to try to grab her attention to talk solutions but she did what she has been always doing lately which is walking back fast to the room and locked herself. I could not have time in those moments to even give her the gift I got her and some magazines for her to see the outside world through because she does not have a TV in her room nor any technological gadgets nor a mobile or anything of that sort. Whenever she goes quickly to the kitchen she takes food back to her room and when she opens the room, she locks it back so no one enters her room but we could smell how bad it is because she has been isolating herself for the past seven months in this manner. I do not know what to do. It has been easy for many people, family, friends to tell us that she needs to see a doctor but we all know that. But how can we do that when she refuses to talk to us? One doctor my family went to, urged them to take her by force to the doctor but I refused thinking it is an extreme measure. She has had hallucinations and was on anti-depressants too.