Hi I'm new here but saw this post
Was in a similar situation before only was just me and my partner in the property
Rave music every night, drugs at the property going on and like you was told neighbours hated us as soon as we had moved in.
This is one of the most difficult situations to resolve trust me. Building a case is very difficult and ultimately we tried but we're forced to move in the end.
It started affecting my partner's and family members health so I cut my losses and moved.
If this were to happen again though, don't listen to others peace advice on here, the council are a load of rubbish and do nothing to assist, ask for evidence that is just impossible to capture at the times they want, we got the police involved he was always out when they came to question him....
Honestly if I was in the same situation again I should've done what I wanted to do in the first and give him a good hiding, police won't do anything unless a crime is recorded, councils are weak and don't enforce.
Make their lives a misery instead report the alcoholic to police and claim you have seen bottles around the property and you fear for your kids safety
As for the big chav, there's ways and means of dealing with people that act hard in front of women, plenty of people will take £100 to hospitalize him just need to know where to look there's always someone bigger
They will force you out unless you stand firm
Good luck