So, a slightly complicated situation but I'll try to keep in brief.
4 years ago my DF passed away suddenly. He had been married to my step mother for about 2 years when he died. A trust had already been set up which granted SM a life interest in the family home and, upon her death the property would pass to my older sister.
SM very quickly decided she wanted to sell the family home and move away. She put the property on the market without any real consultation and accepted the first offer made which was significantly below the probate valuation. At the time, I decided that as she was grieving (we all were), that I would let her carry on. She made it very difficult as she went ahead with all of this without solicitors or the trustees knowledge. Part of the reason we reluctantly agreed was that she wanted to move back to where she was originally from and I felt for her in that respect as she would otherwise have been quite isolated.
After selling the family home she purchased a new property using the funds of the sale. She assured us that this was the perfect place and she would be happy there. Shortly afterwards she decided it needed to be extended.
She didn't consult the trustees or give us any input but she did email us saying that she was spending her money on the extension to make it a lovely place to live and she would never want it back etc.
Fast forward a couple of years and she wants the money back. She says she needs some cash, presumably having spent around £100k she was also left by DF.
Since springing this on us she has proceeded to push and push and has now sold the 2nd house and purchased a third.
All of the above is incredibly frustrating but bearable. Now we come to the AIBU section. After selling the second house and buying the 3rd there is £65k left over. She was initially trying to get all of that, but we've pointed out that some of the increase in value would have been due to inflation. This has gone on and on and the money still hasn't been split.
AIBU to use the email she sent saying she didn't expect any of the money back and/or to push for my sister and I to get a decent amount of inflation.
Thus far she is suggesting 2% p/a which is far below the stats for the area.
I can't decide if I'm being overly emotional and stubborn or if we really need to take a stand.