I have checked my credit file earlier in the year which is how I discovered the default!

Hi I hope I have posted this in the correct forum. I found out at the beginning of this year that a close family member had taken out a credit card and catalogues in my name and defaulted. I believe the credit card has been settled (their word only) and payments are being made on the other debts. The problem is myself and fiancé have been saving hard for a house deposit and will now be refused a mortgage! is there anything I can do to get these defaults removed without getting family member in to trouble? any help greatly appreciated!