Hi jgnat,
Forgiving should be all the time. Associating with an unrepentant wrongdoer is another story. How many times have I heard, "you're supposed to forgive me!" I do, but I don't have to associate with you.
If we find ourselves not able to get along with anybody except on a public message board, we may have to consider that we might in fact be the reason for that, not the rest of the "fellow slaves".
All who have been disfellowshipped cannot be stopped from entering Kingdom Halls and singing Kingdom Melodies with "fellow slaves". The choice is up to you - go to meetings and continue trying hard to run in such a way to attain the prize, or give up. Nobody can force another to serve our Grand Creator and worship Him in the way that he sees approved.
When we start blaming others and fighting, we are no longer serving our Creator. Even if you are the only one serving God in the hall, should this be a reason for you to stop?
(1 Corinthians 9:24) Do YOU not know that the runners in a race all run, but only one receives the prize? Run in such a way that YOU may attain it.