How do you deal with people who do nothing but bug u..
People who undermine your decisions and try to outplay you by saying “but so and so said this.. dont they have more authority than so and so…”
I used to be a nice person once upon a time… but people like such are making me become really stubborn and rude… I just cant tolerate them..
how can I simply ignore them? or not let them get to me 
Source
Here are some of the most common techniques people report using:
**Maintain a task focus **
Be sure that your conversation is focused on the job at hand, rather than the people involved.
By keeping the conversation away from your thoughts and feelings, you prevent the other person from developing a closer relationship with you, and you avoid possible topics of conflict that are unrelated to the minimal interaction you must have with that person.
Avoid questions
This gets the interaction with over more quickly.
But don’t avoid any questions that pertain to the job that needs to be done, unless you can just as easily get the necessary information some other way.
Use a more distant channel of communication
Calling a person on the phone instead of talking face-to-face, or sending a memo or e-mail instead of making a phone call reduce the interaction more to information transmitting than personal contact.
They are often effective at conveying the information that needs to be communicated, but may avoid unpleasant personality clashes.
Be polite
By treating another person with appropriately high levels of politeness, you interact with the other person more as a role than as a human being.
By making the interaction more formal and impersonal, you keep the relationship more distant, and you avoid antagonizing the other person.
It is important if you use this strategy to avoid being patronizing, which would insult the other person.
Involve others in the interaction, when possible
Perhaps save a conversation with this person for before or after a meeting, at a time when you know others will be around.
If others are involved in the conversation, your interaction with that person is “diluted.”
It is also easier to end the conversation quickly after concluding business by striking up a conversation with someone else present.
Do things to make the interaction go more smoothly and quickly
Be sure that you have a clear agenda and have gathered all the necessary information before contacting the disliked person.
That way, you don’t drag the conversation out by doing tasks that could have been done away from that person.
Avoid emotional involvement
Don’t invest a lot of emotional energy in the interaction with that person.
Think of the interaction as just one aspect of the job, do it, and then focus your energy on more positive things.
Hatred is an emotion that grows rapidly and can consume a person if not contained; one way to contain it is to avoid feeding it by stewing over our dislike for someone.
Try to Remain as Neutral as Possible
It is best to avoid antagonizing the person you dislike because that can set the stage for retaliation on her or his part (with just cause!).
Beside, many of the people we dislike, don’t feel the same about us. They may be ambivalent toward us or even think positively of us. Treating them with hostility will only serve to make them think less of us.
There is no point in making matters worse by creating an enemy where none previously existed.
Don’t worry about what other people say. Just worry about doing your job and doing it well. Make sure you follow the guidelines that have been laid out for you. As long as you meet numbers and reach goals you will not have to worry about anyone. If anyone says something to you as wrong as you know it is, let it go in one ear and right out the other. Don’t argue with them. Just try to do your best.
I work with a LOT of lazy people, and that is how I deal. At the end of the month, I always kick everyone’s butt with the highest numbers. That right there is satisfaction. Than I do my victory dance, and enjoy the looks of disappointment on their faces. 