It was agreed upon I'd be living with her, in her home. 3 of the 7 yrs it was a 24/7, 365 days a year decision I made to assume responsibility. Frankly I gave up my life/even my individualalty, that separates us for anyone else in the world. Around 2 1/2 - 3yrs later my father, his girlfriend (now stepmother) and her two granddaughters also moved into my grandmother's home with us. My father, who had COPD, steadily continued getting worse and worse in every way just like, his mother.
If dad is getting worse, you're in line to take care of him too. I don't know what you mean by continued at the end of your post, since I don't see a continuation. In any case, my advice is to get out of there and find your own place to live. You have nothing to gain from this arrangement and much more to lose all over again.
If it is hearsay agreement, then unless you had witnesses to it I doubt you could make a claim.
And even with witnesses, any non payment AT THE TIME not made, and your not filing would play against you, I am afraid.
Also there would be statute laws.
You can take whatever documents and proof you may have to an elder law to see if you have any options and I sure wish you good luck.
Is this really about inheritance? Did you make an assumption about inheritance when your Dad passed? We had a similar issue in my husband's family: his Dad passed away and my BIL assumed he'd be getting an inheritance and was shocked/angered that it all went to their stepmom.
If grandmother is still alive you can still walk away. There is now a DIL. If the DIL does not want to care for GM she can place her in LTC.
Do not look at this woman as a stepmother, she did not raise you. She is ur Dads wife. You owe her nothing. Unless there was a contract, you will get nothing now. You were used as a slave. You owe no one anything. It will be hard but you have to work to get yourself out of this situation. It will be hard but so worth it in the end.