Here's the problem that I have with dramatic irony.
We, as the audience, know that everything that Walt has done has been for his family. Even when he's only trying to convince himself, we KNOW that this is the reason he's doing all of this. From making the video at the start of S1E1 to trying to convince the vacuum guy to give the money to his family...it's always been for them.
But they don't know this. They don't get why he killed all the people over his time as Heisenberg...nobody killed was an innocent by any stretch...were killed to protect the family, his money and his legacy.
Skylar has never understood this, she only saw the legality and never the truth. Junior was fine and dandy driving new cars and shit, until he found out the truth. The truth? He won't even talk to his father, so he only gets one side of the story....and hangs up when Walt tries to explain himself. The only character that has at least SOME understanding of Walt and his motives is Jesse, and he is so blinded by hate that he doesn't see anything else.