And she certainly doesn't owe it to him to expose her sons to his crap. Addiction is absolutely a disease and you get treatment for diseases. Liz can't do that for him, only he can. And right now, instead of manning up to his problems, he's downing down, blaming others and trying to heap guilt onto her. So, frack him.
But agree that Jason was unnecessary in that moment. He should've just ran into Liz after the fact and been like "Jake called me and said you might need me". Would've accomplished the same things without him acting like a caveman.