This is only possible by mutual agreement (the banks are often willing to negotiate, as getting a little is still better than getting nothing) or by challenging the charges in court (they really seem excessive to me).
One precludes the other. In both cases it might be advisable to engage a lawyer.
And you should learn from it: Running away never solves a problem, just makes it worse.
You should have talked to the bank in 2010 when you lost your job!