I understand where you're coming from completely. IMHO do not let him get a second mortgage on your house. He cannot be trusted right now and he proved it by asking you why you do not trust him. The fog is thick and he's confused. You and your D need the house as some measure of security.
My H's memory is shot, too. He seems to have times of clarity and then times when he is there in body but not in his mind. It's very strange.
I'm sure our more experienced DBer's will be along to give advice and opinions.
