What are my rights as co-owner of house ?

Mum and I co-own house with another sibling who takes no interest in the home,and has lived with husband and son in a different county for > 20 years. Since July 2016 I found myself in the position of carer for mum who has severe mobility issues, taking care of all her personal needs,cooking food,meals,washing clothes,all housework as well as all my own daily needs and doing a full time job ie I am working. Mum told me she is greatful for my all my help and the monthly 'house money' I used to give her she started to give back to me from July 2016 except for the odd month here and there when she said she needed money for bill or something. By chance, this weekend when throwing out some papers I found a draft of mums will in which she has left her interest in our house to my younger sibling who is not on title deed. When I told mum what I had found she became very nasty towards me and demanded I pay her house money from next month, I said I wasn't going to because I didn't want her to hand over the money to younger sibling who has joint account with mum and has been mishandling mums money (ongoing problem which mum doesn't want to do anything about- an example is the fact younger sibling has allowed over £300 bank charges to accumulate over past year). Mum has threatened to take me to court and get me evicted, and said she will tell the courts how I dont give her any money !! She has also threatened to go to my employers and get me sacked. Mum is angry I read draft will and seen that she has left younger sibling her interest in the house and as I live in house which is my home and donot and never had been on friendly terms with younger sibling, I have been left feeling very vulnerable and anxious. Sibling who will inherit mums share is single parent whereas I am childless. Mum never asks other co-_owner to make a financial contribution towards upkeep of home,despite the fact home is old and needs lots doing to it. Can mum throw me out ? What rights if any do I have ? Can I fight this ? Mum keeps referring to me as her 'tenant' even though my name is on title deeds,and I have said to mum tell me what bill you want me to contribute to eg electric/gas and I will pay my share, I just don't want to give you money for you to hand over to younger sibling who is unable to manage finances as her allowing £300 in bank charges on joint account is but one example - I reminded mum that only HER money goes into joint account and sibling wouldn't dream of treating her own bank account like that. Mum said its not my business what she uses my money for. Mum refuses to hear a bad word said regarding younger sibling and I am feeling very depressed and anxious. Can you help me please ? And how can I get other co-owner to make a financial contribution ? Thankyou