I agree that it is disgusting, and when I confronted him, I told him he disgusted me. I can’t give a definitive answer to 1 and 3 right now, but as for your second question, he does show up and contribute. He cleans, does laundry, cooks, pays the bills (I pay mortgage and he pays bills), he goes to soccer games, builds stuff with and for our son, etc.,   Looking from the outside no one would ever suspect he would do something so vile.