sounds like you are plugged someplace downstream from the comodes or if you have a septic tank it is full and needs to be pumped.

did you check to make sure the vent is unobstructed?
I am thinking the gurgling could be the water being sucked from the traps.
IF The washer is the only thing causing problems I doubt there is a blockage in the line.

This is kind of what my problem is--not exactly but similar. What the heck is a vent????

The vent is the part of the sewer line that goes straight through the roof to open air. It vents sewer gases and allows air in the sewer line when liguids go down the drain.

How do you check to see if a vent is blocked???

The link below is a diagram of a drain and vent system. The pipe in the middle is the main vent that goes through the roof. The pipes that connect to the main stack above the fixtures are the vents for the fixtures. The easiest way to check if is blocked is run a hose down it to see if it goes to bottom. If it doesn't then you will need it routed out with a plumbers snake.

Here is a link that might be useful: plumbing vent diagram