How to deal with a self-centered bitch

I have a birthday ritual and this year the girls decided that they will join me on my coastal journey for it. (Unfortunately we had a little self-centered bitch among us.)

The Soft Approach:
Ignore her constant whining, conversation hogging and selfishness.

The Mild Approach:
Take the whiny, conversation hogging, selfish girl aside and calmly explain to her that this is enough and that her behaviour is unacceptable.

The Killer Approach:
In no uncertain terms inform this whiny, conversation hogging, selfish, irritating little bitch that you no longer want to hear any complaining from her. If she insists on trying to take you on, end the conversation with the following: "This conversation is now officially closed."

My experience with a self-centered little bitch:
As I said, on our holiday we had a 26 year old girl that thought it is ok to be inconsiderate, talk about herself incessantly and complain non-stop.
Day 1: She takes 40 mins to brush her teeth (thus we are 30 mins late)
She complains she is tired (after sleeping in the car on our drive to Ballito)
Talks the whole day about how stressful her job is (shame)
Day 2: Once again everybody has to wait for little miss go-slow
Talks the whole day about a local she met ... incessantly
Complains non-stop about being tired
Day 3: 5 mins from our destination she wants us to take her back to Ballito to go meet "her guy"
At our destination she bitches to a friend and I snap
Day 4: Never had such a fantastic day... she didn't complain once! :)