A kind hearted person is a joy to be connected with. Here are some warnings of the other kind from an article by Lesli White on Beliefnet.com:
One of the biggest indicators of a bitter heart is a person who holds grudges. These people always feel like they are right and believe the person who has wronged them is automatically bad. They also have a tendency to justify their bitterness as appropriate and well-deserved. They think that because the person has done something so hurtful and insensitive, they deserve punishment. One of the big issues with this is that the anger that comes along with the grudge is often disproportionate to the wrong that was done. Often, they’re not just punishing a person for what they did but also for all the same wrongs other people have committed against them. They hold so much anger and resentment inside, it can really tear them apart.
People with bitter hearts are often narcissistic and experts at creating confusion, chaos and conflicts. The narcissistic lover with a narcissistic personality will create turmoil on a regular basis and on purpose to keep you in a heightened state of anxiety. He or she will do this even when things are good so you don’t expect the relationship to go left or to be kicked to the curb. This is why the silent treatment always catches us off-guard, sending us into a tail-spin trying to figure out what happened. Creating chaos is one of the oldest narcissistic tactics in the book, next to the silent treatment and is absolutely intentional.
Bitter people are often jealous of what other people have. Most of the time, this is a result of their insecurities. They are not happy that other people are in better positions than they are and many times they can’t even hold back their bitterness. Sometimes, jealousy can even bleed into their relationships with others. Have you ever heard jealousy signals passion? This is a very common misconception, especially in relationships of emotional abuse. There is a difference between a partner who cares a lot and a partner who gets upset and controls a lot. While your partner’s jealousy may appear like they are extremely passionate about you, it signals major issues of insecurity and control. Constant jealousy, rage or envy is not only unhealthy but will tear your relationship apart.
You would never think it but people with bitter hearts are experts of flattery. They want other people to think that they’re better, more attractive, more interesting and smarter than everyone else. In the initial phases of a relationship they tend to tell whoever they’re dating that he or she is wonderful, attractive, interesting and smart, because they think that it reflects well on them: they’re marvelous, so they choose marvelous partners. The trouble is that they can’t deal with the inevitable result of what that proves: your development of affection for them. So what do they do? They flip the script. The minute you start getting close to them, the fear of exposing their intrinsic lack of their ability to love starts to kick in and they’ll begin to push you away, leaving you confused, upset and in pain.
If your partner is constantly consumed with their life and their needs, proceed with caution. People with bitter hearts will take advantage of you. They play on the kindness and sympathy of good people, and then try to mislead them. They will demand mercy, but never give any themselves. They will also push for warmth, forgiveness and intimacy from those they have harmed with no empathy. They also have no real intention of making amends or working hard to regain lost trust. A partner that does not concentrate equally to both individuals in the relationship will not change their priorities down the road.