Pretty sure written out of the will

The short version of a very long story is that due to my disability my mum thought I would be near her forever. She owned a business and my sister and brother worked for her. I didn’t as fought very hard for my independence. When she sold the business she gave us all money. At the time I had just met someone. So with the money I bought land to build townhouses. I got promoted fell in love. My parents retired to a warmer climate. Wanted us to move. We said can’t. The property I brought had a caveat and I had signed loan document. Intended to protect me in case relationship failed. Because I didn’t want to move she called in the loan. Said she would never be in the same room as my partner. Cut me off thinking I would fail. 10 years later we are still together and very happy.

I have tried to mend things. She says I made a choice and I will suffer the consequences.

So. My question is. The will outcome is going to be a shit show. I am not going to just walk away with nothing. When we were speaking I was POA. now I am nothing to her.

Is it possible to mediate this now before she passes ?