Don't worry, he will start eating once she has gone off. What I find so annoying is that the males take absolutely no notice of anything you say or do while they are in this state - they are like things possessed. Please be careful
when you do decide to let them back together, as a dog will still try to mate a bitch for several days after she has finished. I had an accidental mother/son mating on day 30, after the dog had been in kennels for three weeks. He came home and I found him tied to his mother on my bed.
I didn't think anything would come of it, but she had five puppies (turned out one of the best litters I have bred!).
The only way is to put him in kennels or get a friend to look after him (although he needs watching as he will try to escape from anywhere to get to her). The bitch will start to reject his advances quite violently after she has gone over the 'crucial' time (trying to bite his face off) but he may still try. As for the barking and howling, welcome to the world of dog breeding!