Guilbert . . . debt (loans, credit cards, mortgages, mobile phone contracts etc) are primarily registered against the person and what you describe is likely only to happen if loulou and the other party are already "financially associated." Contacting each of the three credit reference agencies and CIFAS should prevent loulou's credit file from becoming adversely affected.
Once the records have been noted, any applications processed where credit reference data is sought/verified will be "referred" back to the lender/credit provider. Usually an underwriter is assigned to the case and who can then discuss this in more detail with the applicant.
If loulou wishes she can add a"notice of correction" to her credit file. (The agency will advise how to do this).
If loulou applies for loans or credit, she should be "up front" and advise whoever she applies to of the situation regarding her Credit File before submitting a formal application.