It sounds like your dad said mean things to you when you were a kid, divorced your mother, and won most of the assets. After finding out you were terminally ill, it seems he offered to give you money, sent you some, then later decided to no longer give you money and even sent you a letter to inform you so. It also sounds like you got into some drama with his siblings in which you gave them information about the amount of money your dad gifted you and their scheme was to take money from your dad, rightfully or wrongfully.

I am not sure who to believe because we do not have your dad's side of the story. We only have the words you have heard from his siblings that want the money that currently belongs to your dad. People will behave differently and dishonestly when they want money. They will say and do a lot of surprising things.

I am sad to hear about your story. However, you are 32 years old now. Your dad is not required by law to support you with money. It was only when you were under 18 years old. You are not entitled to his money just because you are his daughter and you are terminally ill. I am sorry if my words hurt you. However, if you happen to somehow win against him in court, then congratulations.