I too hope the castration has the desired effect, but I'm going to stick my neck out now.
I have to agree with Dessie, sometimes finding another home is the only answer. I did it for Georgia and Otis, if I hadn't I would have had let them live a life of misery.
It absolutely broke my heart to let them go but Georgie never looked back (quite literally) from the day she went, and Otis is in his element being an only dog, I know this as I do a 50 mile round trip every 6 weeks to go and trim him.
Contrary to what some people say, I believe letting a dog(s) go is not failing or giving up, and as hard as it is, is the most selfless act you can do when things aren't going right.