Maybe he gets turned off when she's always initiating. She should chill out and let him make the moves for a while.
Totally normal--she should learn to enjoy masturbating or else find a guy who can keep up with her libido.
He's clearly no longer attracted to her. She she should dump him.
There's clearly something wrong with this dude. He should see a professional (a doctor, not a prostitute).
There's clearly something wrong with this lady. She should take up bridge or crocheting.