A bit more of my story, but I need help now please...

Does anybody out there understand Canadian Family Law and maybe how to fight legal badagering? A quick overview of my issues... 2004 I find out my ex has been cheating on me for our entire relationship, I tried to overlook it and we do councilling. 2005 Her oldest daughter who was big in to drugs, drinking, and working the streets threatens to kill the 4 other children and gramma one night, so I said the daughter had to get help and live elsewhere until she did. The ex decides that her troubled daughter was more important than the family (yes the ex has many personal issues as well) her other daughter and our son (along with her boyfriends) and moves out saing "she just needs space" but drags he other daughter and our son with her. So teachers (against standard policy), coucillors and several judges agree that at least our son should not live in that environment and should live with me (dad), mom finds free , moraless and unscrupulus lawyer who in last count dragged me to the tune of 10's of thousands of dollars to 7+ judges and court proceedings to get our son on a 7 day rotation (I wont tell you here what this has done to his life or schooling). (The ex also dragged her other 3 childrens 3 fathers through hell to the point where they basically dont exist in the kids lives). So now Im broke and doing my best for our son and the kids I can help. Lots more story.... anyway I bring you to today... My house burnt down May 1st 2010, I was stupid enough to put her name on the house along with mine but other than outright taking the house from me she would settle for nothing and would not take her name off, she has no posessions in the house and has not lived there for 6 years. After the fire she signed off on conents and living allaowance with the insurance company, which I thought was great. and we would deal with the structure seperatly. Well now she has trying to get her lawyer to withdraw that agreement and she wants control of the living allowance and content monies. Which would essentially at this point put me on the street which as I see itat would now show me as incapable of taking care of our son and probably remove him from me (I may be wrong in my thinking here, I am not her, maybe she only wants more money, both in insurance and support). So what I hope someone can give me insight to law or canadian law as how she has any right or claim to something she has no (what should be) legal interest in. I cannot afford a lawyer, so I will have to represent myself. I hope I make a little sense in what i wrote, the story is much bigger and longer, but anything will help. Thanks