My boyfriend of 12 years wants to add me to house title. His lawyer refuses to do it.

We also have two daughters together. I sold my home and he was supposed to sell his, and us buy a place together. However, due to repairs to be made on his home, his couldn't sell. Consequently, I moved into HIS home, where only he is on the title. Over the years I have spent $25K out of my money fixing his home up to sell. Also, I have paid 3/4 of the bills in HIS home and everything for our daughters alone because I make significantly more than him and he is always unemployed. I told him that I am going to move, because basically he now has a nice house paid off because of my financial efforts and I have nothing. He visited his attorney about adding me to the deed to his home, giving me a 20% interest and his attorney flat out refused to do it, stating that we are not married and "I don't care if she pays all the bills in your house. She's not your wife. Your better off giving 50% to a noncontributing spouse than 20% to a contributing girlfriend". Why is that?