Can my spouse move their new partner into the matrimonial home while we're separated?

There is no automatic legal rule preventing a separated spouse from having someone else in the matrimonial home, but the circumstances matter greatly. If there is a court order governing possession — particularly an exclusive possession order — that order may restrict what the occupying spouse can do with the home, including moving others in.

If there is no exclusive possession order and you are still living in the home, your spouse moving a new partner in without your consent creates an untenable shared living situation. This situation can support your own application for exclusive possession, arguing that the changed circumstances and conflict make continued shared occupancy unreasonable.

Where children are involved, courts are particularly concerned about new adult relationships being introduced into the family home during the separation period, especially if it disrupts the children's wellbeing. This can be a relevant factor in both the exclusive possession analysis and in broader parenting proceedings. If your spouse is moving someone new into the matrimonial home and it is affecting you or your children, discuss the situation with a family law lawyer promptly.