My heart breaks for you. I SOOOOO understood the statement that you don't trust anyone to love them like you do. I feel the same way about mine.
I wish I had great advice to offer but it sounds like your new plan might be the only thing there is left to do. I also think that Bisi.cat had some good advice about seperating Noah so Livvy can relax. It is amazing that a sweet good natured cat can just turn on one cat for no reason. I guess they conflict like people.
I'm sending prayers because that is all I have to offer. Bless you and keep us posted.