<human>: Can you give me the gist of the text in a nutshell?

This is in Edmonton, Alberta.

My ex and I bought a house together 1.5 years ago so we are joint tenants. The mortgage and title are under both of our names.The mortgage payments have always been automatically withdrawn from my personal bank account. During the course of our time together for 2.5 years with a house, she never made a single mortgage payment to me. 

She is threatening legal action towards me because she wants half the equity, and I know that technically this could go to court. So my question is if it goes to court , can I make a legal argument that she never paid me a single dime for the mortgage during the course of our tenancy together and therefore disallow her from claiming her "share" of the mortgage?
<bot>: ex and i bought house together, no record of her ever making a single mortgage payment to be, if it goes to court, do I have a legitimate defense to argue that none of the house belongs to her?