Hi MolloyR
I too am going through a marriage break up and am taking over the mortgage which I have being paying since separating. However, both of us are working and the outstanding mortgage is under 100k.
You will have to go to your lending bank and discuss the matter with them.
In my case, I had to make an application for the outstanding mortgage. The bank took a number of factors into consideration before approving my applicaion, i.e the amount of the mortgage outstanding, the duration, my age, my ability to pay, etc. A credit check was also carried out on me. When they were satisfied that I was in a position to repay, they consented to my partner's name being removed from the mortgage and the deeds subject to me submitting a copy of my Deed of Separation and Deed of Waiver.
I hope that some of this information may be of help to you. As you can appreciate this is based on my situation, it could be different for you.
The best of luck.
Windy