Hello Pinky,
I am sorry to hear that your mother is resistant to getting help.
Ordinarily in such a case the technique of "motivational interviewing" helps, whereby you develop a relationship of trust with your loved one, find out what his or her goals are, and when the person seems receptive, you offer your idea that if she was in treatment, she would be able to achieve her goals.
From reading your question, I'm not sure that your mother has goals. Maybe they simply haven't been articulated to you. It is possible that with a little coaxing you can find out what her dream is, and begin to talk to her about how she can make it happen.
You say the hallucinations would happen at least once a year, and that is only what you've observed, so it's entirely possible you weren't aware of other episodes. You were young, a child, and so likely wouldn't have understood or known the severity of what she was going through if you also had to work on the everyday activities of life growing up as a kid. From what you did know as a kid, it must have been upsetting if not painful to live with a mother who had a mental illness.
What I'll say is that you need to just be there for her, talk to her, develop her trust so that you can suggest she see a professional. At this point, it doesn't have to be a doctor, it could be a knowledgeable social worker who meets with your mom and then feeds back what he or she thinks is going on.
You are in Indonesia, right? Maybe there is a bookstore there where you can buy Xavier Amador's book, I Am Not Sick, I Don't Need Help. He is a psychologist who guides family members in how to coach what they say so that a loved one is influenced to seek help.
I'm sorry to report that there is no quick or easy solution, especially not to a problem that has been going on for quite awhile. Even with a newly diagnosed person who refuses to take meds, it's an uphill battle to convince them.
The main thing is, refrain from telling your mother that she's sick and needs medication. That is a no-win situation. Only bring up the idea of medication after you've gained her trust and you have an opportune moment to suggest what you think might help her feel better.
As you've guessed, the more you try to convince her she's sick, the less likely she is to listen to you.
So I believe reading the Amador book would help as a good first start.
If Indonesia is anything like the United States, a person can't be admitted to a psych hospital unless she is clearly a danger to herself or someone else. When you feel her life is in danger or that her symptoms have gone too far, then you have to make the choice as to whether you claim she's a real danger to herself or to you or to others.
I wish you the best in what you are going through.
Change won't happen overnight, yet it could happen.
So never give up on your mother.
The tide could turn at any moment.
Regards,
Chri