I totally understand how you feel sunnybean as my mum did the same thing and left everything (although very little) to my brother.
It was a shock and even though it came as no surprise, like you are feeling now, I was hurt. My mum died last year and my brother had already estranged me to the point that he didn't tell me she'd been taken into hospital, and got one of our cousins to 'phone me to tell me that she'd died.
I was told that there was no money to pay for her funeral and that unless we were prepared to foot the bill, he'd go to social services for funding.
We took it on and that is something I will always be thankful for. He didn't attend and it gave me the opportunity to say my final 'goodbye' the way I wanted and how I believe my mum would have wanted too.
I know that there were a few personal items that were still left to me, but as I already had her engagement and eternity rings bought by my father, I decided that those are enough and have never contacted my brother about any thing else.
It will take time for you to fully digest this and you may find, as I did, that finding out before your mum dies is preferable to finding out when she does, and you are trying to come to terms with her loss.
Please feel free to private message me about this any time if you need to talk more privately
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