Maybell - I feel for you - we had an lice infestation a couple of years ago that did not become apparent until pretty late in the game. Both girls and I had it and I didn't completely eradicate it from D7 for four months. Still have a drawer full of various lice combs. Apparently 70 % of lice has become drug resistant so it's basically endemic now. Shudder.
Keeping my fingers crossed that you all sleep with clean, clear heads tonight