R.J.
You DON'T speak to your mother that way. Timeout.
This is the new mantra. You need to get dad on board, because the MOMENT he does it to you (says go away, etc), he needs to 'go cold' put him down or disengage, and kiddo goes to his room.
Is favoring normal? Yep. Is it acceptable? ONLY when done in a way that is NOT disrespectful, hurtful, or demanding.
Can daddy tie my shoes, please? Is okay
Not You!!! Daddy! is NOT okay
I love you daddy! Is okay
I love you more than mommy/ I hate mommy/ etc. is NOT okay
Daddy!!! Yay!! Is okay
Daaaaaaaaaaaaaddy! DaddyDaddyDaddyDaddy. (tantrum for daddy) is NOT okay!
Get the drift?
If he's rude to EITHER of you, he gets neither. That is NOT how we treat people.
He can love his dad WITHOUT being rude, mean, disrespectful to anyone else.
Dad REALLY needs to be on board with taking up 90% of this, because everytime he let's it go he's telling your son that that is the right way to treat you and to show love. Aka rewarding him.
And during the day? YOU need to stand up for you the same way you'd stand up for a kid being treated this way by your son.
HINT: kids at certain developmental phases push parents away. It's a test. One, CAN they? And 2, will you still love them? The harder they push, the faster they come back. Something I did was to just laugh at my son and tell him I loved him enough for both of us. It ticks them off, but it also cuts short a LOT. Biggest parenting trick I ever learned was to never get emotionally invested on an argument with a child. Does it happen sometimes? Sure. But it's pretty rare. It is ALMOST impossible for my son to hurt me. He can try, but when it doesn't work, he quits trying. Kids are KING of misery lives company. Don't let it go there, and it will stop. For months and years. Then a new phase brings it back, gets stopped, and they don't try again for a few months or years.