Her mother deceived the state and got accommodation and benefits; does the burden of sin apply to her too?

I come from a large family and when I was growing up my parents began to commit benefit fraud as my mother would claim that she is a single parent in order to receive state benefits even though she lives and is married to my father. As a result of this my family receive free accommodation, extra spending money and many other benefits from the Government. My father also works and contributes to the family expenditure. This benefit fraud is still going on. I only found out what my parents were doing when I hit my late teens. I desperately begged them to stop but they believe that one day they will stop this fraud and Allah (swt) will forgive them without having to pay back the money. I am aware that I also consume some of this haraam money but I have no choice as my parents will not stop this fraud. They still continue doing this so half our family income is halal (my father’s wages) and the other half is haraam (money stolen from the Government). I spoke with a pious relative about this matter and he said that as I also consumed this haraam income I am required to pay back all the haraam money that I used from the age of puberty onwards in order to seek Allah’s forgiveness by returning that which belongs to someone else. Is this true? If so, how do I estimate how much money I need to give back to the Government given that I was also brought up with some halal money? Do I assume that my father’s income paid for rent so I should pay back all the extra money the Government gave my mum for each child? Do I need to return all this money to the Government before my Hajj can be accepted? This money will take me a very long time to pay back. If I get married to a rich man, can he pay it back or am I the only person who can pay back the debt as it is my debt? My parents are very private about their money but openly admit to unlawfully taking someone else’s money. They still commit this bad act today. I began working full time a few months ago and I pay my parents to live at their home. Will Allah(swt) accept this from me (i.e. my wages pay for all my living expenses so that I do not consume any of the money from the fraud that my parents do)?
My parents refuse to stop this benefit fraud and I do not know what to do.