I cannot afford to pay my loan repayments due to change of cirstances?

my account is going to the recoveries,i owe about �15,500, i was told that if they dont except my offer it will go to a debt agency, who will then agree an amount, they also said that in rare cirstances they can force the sale of the house! but the loan i took out was an unsecured personal loan! is this true? also my partner owns the house aswell? any advice on any part of this matter would be much appreciated?