what to do?

everywhere i go, everyone i spoke with told me i needed to get a domestic helper to help take care of mum. this was the same input given by the rehab center, by the hospital, by my bro, by the hawker uncle, by my friends, by my neighbours, etc. and i think they are right cos my mum is really robbing me of my life. everything i do these days are centered around her. and after quitting my job, all my time are committed to her and her well-being. yet despite all the efforts, i end up getting her black face and her venting day in and day out. i am really going crazy. now, let's review the reasons why i had resisted getting a domestic helper. 

it was becos my mum had paranoia and delusion. thus, she has this constant suspicion and fear of people that she is not familiar with. for that matter, even for people she is familiar with, but not considered her immediate family members (read - her children), she has this deep suspicion about them. when she stayed with my bro, we had a domestic help looked after her. but over time, she suspected the domestic help of using black magic on her, she even suspected my domestic help of conniving with my sis-in-law to kill her. so much so that she went berserk - yes, she was no different from a totally crazy screaming woman - asking to leave the house immediately one evening while i was still at work. 

my brother was at his wits-end and wanted to send her to the mental asylum. he called me to help and i had to rush to his house to talk to her. that was how she landed in my house a year and a half ago. and since then, she had stayed with me. during this year and a half, she had plucked the door peep hole, locked every door that can be locked when she is at home, closed every window that can be close at night. i have had many occasions where she went crazy for no particular reasons other than her paranoia and delusion. she imagines she sees things. she imagines people are out to harm and kill her. when she first came over, bee stayed with me half the week. but over time, she also got suspicious of bee, accusing him and his mum (for god knows why) of wanting to kill her. and that was how bee stopped staying with me. and for that matter, she also suspects my movements for she asks me non-stop what i was doing whenever i leave her sight when i was at home. 

it is precisely becos of all these that i had resisted having another person in the house and end up having to manage her alone. am i wrong? should i proceed and get a domestic help? everyone seemed to think so. but everyone is not aware of how suspicious she can be and her over-the-top behaviour. i am very certain she will end up suspecting the domestic help will want to kill her too. but other than this, what other solutions are there? medically, the doctors have adjusted her medications. and other than her mental issues, she also has the respiratory issues, her pain management issues, her internal medicine issues, etc...

what should i do?