Sometimes, when couples separate, one spouse stays in the matrimonial home for years following the separation, even when they are not on the title to the house. While it’s not unusual for one spouse to hold the title to the house in their name as sole owner, if you are planning on living at the home, and taking over the mortgage payments after separation, you need to arrange for the transfer of the title of that home into your name, as well as your assumption of the mortgage (assuming the lender will consent to this assumption) as soon as possible. If you’ve been unsuccessful negotiating this with your ex, then you need to consider starting a court application.
The fact that you’ve continued to live at the property for a long time and paid the mortgage doesn’t mean that you acquire title to the house at a certain point.
Under the Family Law Act, both spouses have an equal right to possession of the matrimonial home. If you ever stop paying the mortgage and it goes into default, the lender is required to provide notice of default to you, as the spouse of the mortgagor. Additionally, as a spouse in possession of the matrimonial home, you have the same right to redeem a mortgage as the mortgagor. You lose this right to notification and redemption once your spouse obtains a divorce after your separation.
Your rights as the spouse only go so far if the mortgage winds up in default. If you aren’t able to redeem the mortgage, the bank would list the property for sale and the remaining funds- after payment of the mortgage and other encumbrances- would be paid to the owner/mortgagor, unless, of course, you are successful in bringing a legal action claiming that you are entitled to all, or a part, of those proceeds.