I had extreme noise harassment for 11 years. Then I moved from the city to a rural town where noisy neighbours are visible as anti- social elements - and that problem stopped.
I found the wax ear plugs you get from Boots are the best, combined with noise reducing headphones and music. If I can't sleep at night I listen to music through headphones. noisy neighbours are often criminals. Try and find out what illegalities they are involved with and inform relevant authority. I got rid of some noisy neighbours that way.