I have a question regarding Dark Jolteon's Lightning Flash attack.
If someone attacked me with that attack, will benching or retreating the defending
pokemon take away the effects.  I don't think I should have to flip to attack if I've retreated or switched, should I?  I'd appreciate any answer to my question.
 

You are correct.  Just like Smokescreen, Lightning Flash's effect will end upon going to the bench.

Scott