I'm sorry you are feeling so overwhelmed right now. Can you hire a sitter to come over to get yourself a break? My DH also works long hours and I know how hard that can be.
I have no idea if someone already posted this but here is how you tell a live nit where the baby is still inside from a "dead" one where it has already hatched out the crawling louse.
Stop reading if this is going to gross you out.
Pop the nit between two fingernails - like put the nit in the middle of your thumbnail and push with the other thumbnail. If it makes a popping sound, there was a live one inside. If it doesn't make a pop - it has already hatched - at that point look for live ones. This is from my summers living in India.
Very very bad, suppressed memories are surfacing, thank you very much.
Since there is no 'dislike' button, just quoting to say sorry.