I'm a caregiver who has been asked to leave or be evicted. What can I do?

I have been a caregiver for my then boyfriends parents for 15 months in Texas. The dad passed away on Christmas last year and we have been taking care of his 86 years old wife with dementia. Before he died he put me and stepson in the will to receive the house and contents after she dies to compensate us for leaving Ca to come to take of them, now her sister does not like me and has told this woman to evict me. What can I do ? Disabled myself with no income, no car, no family or friends here. Her son is my ex boyfriend and is living here as well. I'm distraught, need advise please ! Thank you so much !