Hello, Andrew.
I am new here, just jumped on the bus when it was already moving. Didn't see the problems you list yet, but I could see from the tone on this thread that you are a person that everbody likes and respects here.
This kind of behaviour is really upsetting and it happens anywhere online, unfortunately. I agree with others that the best action is to ignore, even though it is difficult when you and the ones you like are being insulted.
Hope you reconsider your decision, cause if you leave it means the trolls are winning.