I live in a townhouse and our houses are pretty well sound proofed, except for bass. I have ADHD and the constant thumping from bass is extremely distracting and it drives me crazy, even if it's not that loud. 

We've been moved in for about 3 years (myself and my neighbor) and in that time, i've asked nicely 3 seperate times to please turn the bass down. The first two times, they were super cool about it, even checked in after to make sure it was better. The third time though... and I quote: "I understand how you feel but it's 6 in the evening on a Saturday. We are allowed to play music during this time and try to be respectful in the late hours which is 10pm so please be considerate of our time to do what we'd like in our home within respectable hours of the day. Thanks." -- which now that I re-read, was much nicer than what they said next...

So last night I could hear it in my room at like 830 pm and I had a long day was trying to rest to get some sleep. So I caved after like 30 min and posted on our neighborhood facebook group to please respect your neighbors, bass travels, a couple suggestions on how to mitigate it. That was probably not the best idea, but since they basically told me to go f'off last time, why would I assume they would be reasonable asking again? They did turn it off, but not before being nasty to me offline and then telling me to move. 'You're more than welcome to make necessary adjustments to your peace including finding another place of residence.'

Legally, they are right, they can be loud all day, so long as it can't be heard more than 50 feet away, so I have no legal grounds to stand on (I think anyway). 

Thoughts on how to move forward? 

I worked with my other neighbor (who is super nice thank goodnesss) when I moved in to make sure my bass wasn't a problem, and I check in every once in a while. If someone were to message me and say, hey I can hear you guys doing x, I would say sorry and stop doing that. I don't understand why that is so hard for some people.