legal rights to property?

What is the name of your state? Minnesota
I married a man 12 years ago who lives on a farm and still owed a mortgage on it. He has never put my name on any of the property. He wants to give it to his two grown sons. We have an 11 year old son together. I have worked on the farm and helped make the payments. What am I entitled to and how would it be devided if somehing would happen to my husband? We have considered divorce but he doesn't think I should have anything if I leave. I also have 3 grown children who worked on the farm when they lived here.