beating a dead horse 

It doesn't matter how much you want to continue riding beating a dead horse is not going to get you anywhere.

If something is already done and over with there is no point in still talking about it.

If something is already broken there is no point in trying to use it.

Someone breaks up with there girl/boyfriend and continues to bitch about them to there friends weeks later. That person is beating a dead horse, the relationship is over there is no point in thinking about it since the matter is already resolved with you having broken up.

Relationship = dead horse
Bitching about it = beating it

Trying over and over to start your car after you've been in an accident where it is clear that the car is not going to work.

Broken Car = dead horse
Trying to start it = beating it

beating a dead horse by Bradley Groot February 19, 2008

beating a dead horse 

When something is already dead, and you keep bring it up over and over again

counter strike is a dead horse that everybody should stop beating

beating a dead horse by Kyle Biddle August 2, 2004

beating a dead horse 

to continue to persue a situation that nothing is happening in.

taken from the act of whipping a horse to get it to move, even though it is dead, and aint going anywhere.

"sometimes I feel like I'm beating a dead horse"
"It's going nowhere, stop beating the dead horse"

beating a dead horse by ChipmunkOnKetamine November 7, 2009

beating a dead horse 

an act of sexual perversion combining bestiality, necrophilia and sado-mashocism.

A government study was funded to study various sexual perversions: sado-masochism, necrophilia and bestiality. The study was soon halted however ... the researchers decided they were just beating a dead horse.

beating a dead horse by Figleaf23 January 4, 2009

Beating Off A Dead Horse 

To continue trying to beat off a horse when it clearly isn't going to work anymore due to lack of blood flow.

Dude: I was out beating off a dead horse last night, but may hand started to cramp up, so i just went home instead.

Beating Off A Dead Horse by XxVRxX August 20, 2010