This article is from a book by Dr. Judith Orloff and contains some well researched material on the various types of people we encounter.  

From "Positive Energy," by Judith Orloff, M.D.:

Certain people give off positive energy, others negative. It's the quality of someone's being, a measure of love with which they've led their lives. It also reflects the inner work they've done, their efforts to heal anger, hatred, or self-loathing, which poison us like toxic fumes. Energetically these linger, precluding joy from shining through. It's important to grasp, however, that once you undertake the process of healing, it changes the quality of even the negativity that remains. Don't be too hard on yourself-we're all works in progress.
SIGNS OF POSITIVE ENERGY IN PEOPLE
+ They exude an inviting sense of heart, compassion, and support.
+ You intuitively feel safe, relaxed, wanting to get closer.
+ They emanate a peaceful glow.
+ You feel better around them. Your energy and optimism increase.

SIGNS OF NEGATIVE ENERGY IN PEOPLE
+ You experience a sense of being demeaned, constricted, or attacked
+ You intuitively feel unsafe, tense, or on guard.
+ You sense prickly, off-putting vibes. You can't wait to get away from them.
+ Your energy starts to fizzle. You may feel beleaguered or ill.

I'm a big fan of being proactive in generating positive energy. The First Prescription's formula for success: Do whatever makes your inner light burn brighter. In other words, try to treat yourself and everyone else with love. It's a constant process of tuning in: finding people who support your spirit, trusting your gut-centered decisions to guide you. Then you won't end up in a relationship that looks right but feels wrong. Or miss the chance to meet a loving man or woman because he or she doesn't fit some preconception. When you're with trying people, aim for the high road; find common ground, rather than inflame negativity. The care with which you approach life is intuitively evident in your energy field. We can feel each other's love: that's the great attraction. Spread openheartedness around.

Oh... so that explains it... but I wonder why still now people feel bad vibes from me? Is that a sign that the changes I had isn't enough yet?... =__=

Our personal energies will always repel some people and draw others.  It is the nature of magnetism which all have within our own energy.  The changes we make to ourselves is for ourselves.  It is about wanting a higher spiritual perspective and doing something about it.

Hi Spirit Talk!
I love Dr. Orloff's writings and enjoyed her perception as I was learning about myself!
For those of you out there that are just learning, you can find her audio tapes and books at the public library to check out.

I have to say, in my years of development, I have learned that when I start to feel the negative attributes of people, It is a sign to me.
The feelings and personality of my own being, will reflect what that person is projecting and it is up to me to recognize these shifts.

Once I recognize I am mirroring another's personality, I realize I am actually reading that person.
Which then helps me, Help them to see their issues in another perception.

Once they change their perception on the situation at hand, they no longer emit such a high radiance of negative energy.

For example: I have a client who was having issues with her neighbor, The issue formed into hate for that neighbor.
The hate grew so much in my client, all the client could think of was how much she hated her neighbor!
The hate took over every other thought in my clients mind, which in turn, took over the decisions she was making in her career and family choices.

The kids felt the anger, the husband felt the anger, the client was then considering divorcing her family because of all the anger in the household.

I talked with my client, I told her that if she could see her neighbor in a different light, the problems within her family will leave.
The client of course could Not get herself to see the neighbor differently, until she was shown the neighbors sadness and loss in her own life.

Once the client was able to understand the neighbor as just another person, who has experienced the loss of a child, the loss of her happiness
The client felt pity for the neighbor.
The client then took the neighbor a potted plant, The plant was an offering to the neighbor to show "I thought of you today"
The neighbor accepted the plant and later that week offered my client a doll.

My point to this is, when we feel negativity from another person, We can see past it if we try.
Therefore, does the negativity really exist and if so, what is our duty to eliminate it?

BTW the clients home life is running much smoother and she has a new friendship that is going on 5 years.

I think that recognizing negative and positive attributes of the different types of people in this world, Helps Us All to Grow within our own searches
What do you think?

Dr. Orloff has a wonderful write up on Psychic Vampires in her books.  It is excellent material for self journeys as well as understanding self from another perspective.  LIfe is all about the energies we emit.  Keeping our own loving is the key.