instead of looking at what might be prompting his behavior, LOOK directly AT his BEHAVIOR. he is being secretive and threatening. he is using money as a threat. he is ratcheting up his anger and hostillity and is showing NO remorse OR concern for how his threatened actions may affect your and the children.
you moved out once before....you can most certainly do so again. children deserve safe happy secure homes filled with love. and that does not happen with an addict on the rampage.........instead of asking why he would choose drugs over his family....ask yourself why you would choose to stay in his toxic insanity instead of putting your own welfare FIRST.