Why do some people use others?

Why do some people take advantage of others?
Why do some people use others to reach their own goals?
Why would someone date someone else then dump him after he reaches a certain goal?

The first thing that will come to your mind when you try to answer such questions is that the people who do those actions are mean. I do agree with your conclusion But from a psychological point of view, why do some people become that mean while others don't??

And why do some people never feel like using others even though they might gain many benefits if they did so?

Here is the quick answer, the way some people developed their personalities forces them to use others in order to maintain their mental stability.

why do some people take advantage of others

Here are some reasons why people are more likley to take advantage of others:

1)Helplessness Any sane human being will use the path of least effort to achieve his psychological goals and unmet needs. When a person attempts to take advantage of another person he will usually experience some kind of inner resistance and that's why many people don't feel comfortable about using others. Now when a person finds no other way to reach his goals but to use others then he might start taking advantage of them. In other words the person who uses you is actually the helpless one
2) Lack of control over his own life: When a human being loses control of his life he usually starts to find other alternative ways that can help him feel in control. For example, some people develop sadism because it helps them feel powerful and in control. One popular way of feeling in control of one's life is controlling others. In other words the person who is taking advantage of you might not have been able to control his own life and that's why he is using you to restore his mental balance (see also The psychology of control freaks)
3) Inferiority: Many people feel inferior to others and believe that they are totally worthless. People compensate for this inferiority in different ways, some of them become arrogant, others claim that they don't like to interact with people while a third group might use others. When a person takes advantage of another he might feel superior to him and as a result compensate for his feelings of insecurity
4) Narcissism, codependency & double standards: Narcissists and codependent people might use others in order to calm down their insecurities and feel better about themselves. In order not to feel guilty or to experience shame those people usually try to convince themselves that some people deserve to be taken advantage of. These double standards helps those who take advantage of others feel better and face those who point fingers at them

How to prevent people from taking advantage of you

I wont ask you to be parniod or to live in fear in order to prevent others from taking advantage of you because by doing so i would be infecting you with another insecurity.

Instead, know that the world has good people and mean ones. That's why you need to be able to understand people better so that you spot mean ones in early stages of your relationship with them. (the links below will help you do so)

Once you become able to do so you can deal with those mean people the way they deserve while remaining kind to others.

2knowmysef is not a complicated medical website nor a boring online encyclopedia but rather a place where you will find simple, to the point and effective information that is backed by psychology and presented in a simple way that you can understand and apply. If you think that this is some kind of marketing hype then see what other visitors say about 2knowmyself.

The Solid confidence program was launched by 2knowmyself.com; the program will either help you become more confident or give you your money back.

Want to know more?

Advice for dealing with mean people

How to identify haters and mean people

How to deal with someone who hates you at work

Why can a jealous person find you unattractive

How to be a mastermind when dealing with people

How to get over anyone in few days (book)

How to make anyone fall in love with me fast (book)

How to end Depression instantly (book)

How to control people's minds (Course)

How to develop rock solid self confidence fast (course)