English to Italian Law/Patents Law (general) divorzio

UK Matrimonial causes act:
For the purposes of section 1(2)(c) above the court may treat a period of desertion as having continued at a time when the deserting party was incapable of continuing the ***necessary intention*** if the evidence before the court is such that, had that party not been so incapable, the court would have inferred that his desertion continued at that time.

Riferimento:
Art. 1 comma 2 lettera c: The court hearing a petition for divorce shall not hold the marriage to have broken down irretrievably unless the petitioner satisfies the court of one or more of the following facts, that is to say [...] that the respondent has deserted the petitioner for a continuous period of at least two years immediately preceding the presentation of the petition.

Come può essere tradotto necessary intention?
permanent intention to remain married è l'affectio maritalis: si intende questo qui?
Grazie