Reply #45: IMHO this is Freudian 'displacement' -

[IndyOp]

Displacement is when you get angry at someone who is a 'safer target' -

If you get angry at your partner then you might have to face that you can't trust them or that you have to end the relationship. Getting angry at the other person is (usually) easy.

Other examples:

If your boss yells at you and you get angry at your partner, kids, dog. It isn't safe to get angry at the 'boss' you might say something that gets you fired.

After a hard day at school teenaged girls tend to take their anger out on their mom (she is safe target - she isn't going to reject you).