That, my friend, is called a Velcro Dog.

You see, in the mind of a Velcro Dog there is such a thing as Gremlins...
Gremlins can kidnap Humans who get separated from their Dog...
Bathroom Gremlins are particularly evil and must be avoided at all costs--thus the reason Velcro Dogs sit outside the bathroom and cry.
To be loved by a Velcro Dog is a great though at times trying thing.
You can assign a specific location in each room for the dog to go to and lay down. It will take training but they usually will learn to go to their spot in each room. This way, at least you won't be tripping over them.
You can also work on teaching down stays and practice going into another room. At first, stay where the dog can see you. Gradually, work toward the dog not being able to see you --first for a second and then work up in time.