You signed a contract to pay the loan.  You owe the money.  

Stories of people being arrested over defaulted student loans are usually based in contempt of court warrants when the person failed to appear in court when the collection agency filed suit against them.

Explore student loan forgiveness program.

Research collections and bankruptcy and how to deal with collection agencies.  There are pitfalls in communicating with them which restart the clock on bad debt aging off the credit report, and which can be used to say that you agreed to pay a debt.  For instance, if you make any sort of payment on any debt, a case can be made that you have assumed the debt.  Once you are aware of the pitfalls, contact the collection agency (in writing) and dispute the debt.  Force them to prove that it is your debt.  Force them to prove that they have the right to collect it.  Force them to prove the amount.  Dispute the fairness of the amount.  

Doubling your principal in 6 years is a bit flagrant.  

So, work with the collectors, establish that the debt is valid and negotiate a settlement.  Or let it stay in default.

Your credit report in the US is shot.  It will be a long time before the default ages off your report.  This is important if you try to open a bank account, rent an apartment, or get a job in the US.  These activities do not always require a credit report, but they often do.  You will not be able to borrow money or establish a credit card in the US.