I had a 10 lb pomeranian humping my arm. Hmmmm. Is she trying to tell me something?
Your dog is telling you that you are her Bitch.
You outweigh that little bitch by an undisclosed but significant amount. If it takes throwing the little bitch across the room to make the point that SHE is YOUR bitch..then do it. Stuff her head into the ground/carpet/grass when she misbehaves until she stops fighting you and gets the point. And stop worrying about your bitches feelings...it is a DOG, not a child. You cant reason with a dog, you have to DOMINATE it...or yes...you are her bitch.
BTW...letting your dog piss on your neighbor's mailbox posts is pretty disrespectful to your neighbors...that piss stinks, and it will eventually rot out the posts...yes...other dogs leave their marks there and your dog just wants to contribute...but YOUR DOG is ON a LEASH...you are in control...or are you?