Ok sounds like our story in life is almost identical!!
I too am estranged from my family since my dads funeral in fact. It was very hard for me to document my genetic history but with help from my overseas relos it was confirmed we have a significant family history not just my mum but pretty much everyone on her side of the family...and little old me the youngest of my siblings.
I too had no support during my journey except for my partner his family and my then 10 year old daughter.
One thing i have learnt is that you cant change how others think. There is no point wasting time on all the negative aspects of your life just move on with your life and live it to the max. I have realised that where family is concerned shit happens and i see no point dwelling on it. I didnt tell my family about my bc because i figured my health struggles are my business. One of my sisters was told last year..coincidentally by the executor of dads estate on the day we auctioned the family home in September.
Needless to say she hasnt bothered to make contact.
Dont stress about others focus all your positive energies into getting better.
Take good care of you
??????????
Maryrose