If you are personally attacked, don't defend yourself. Instead, let other community members defend you; if they don't, shame on them. This may be surprising - but defending yourself is not your job, it is the job of the other members in the online community.
And remember, most of the time personal attacks need not be defended at all, because the attacker only hurts their own reputation and credibility. However, ModelDesiredBehavior: if someone else is attacked, defend them.
While conflicts are typically seen as negative, they hold big chances to grow as a community, to build trust among the members, to grow in valuable experience. Observe and learn for the next conflicts.
Another aspect is, to help each other to protect their work against wipeouts or mutilations by spammers or vandals, but also help each other to transform (who appear to be) enemies into friends. -- FridemarPache