Girlfriend and her Dog moving in! Options

[goodfellow]

She and her 4yo female lab are moving in with me and my 5yo male beagle/dachshund. We'll both have separate bedrooms, though we'll sometimes sleep in my room, sometimes sleep in her room.

Both dogs are neutered and have met and like each other in general. The problem arises when my girlfriend and I are sharing a bed or couch and watching a movie; both want to be right there with us and protecting their respective master, and that's led to some fighting.

An issue with my dog in particular is that he doesn't growl to warn other dogs when they've gotten into forbidden territory, he goes straight for the nipping and biting. I know they need to establish their pecking order to some degree, I just have concerns he'll be too rough.

Is suddenly forbidding both of them in the bed or couch the only way to go?