Alrighty. Here is what I know. The One God is like the fertile soil that nourishes the growth of all life. When a tree grows, it has roots, a trunk, and branches. The root and trunk are the One Soul that we all are. In Truth, there is no separation between us except for the separation that we create for ourselves. We are unique expressions, but eternally interconnected. Every branch hosts more branches. The smaller branches host more branches still. The smallest branches are like soul groups (or "soul families"), each one hosting many twigs which are like "individual souls." Remember, of course, that these "individual souls" only act as individuals because they believe themselves to be separate from the ground, roots, and trunk. When they act as a part of the tree, they are nourished and supplied with all they need to grow. When they cut themselves off from the tree, they whither and die. Only those who act as a part of the whole tree can bear fruit. Note also that fruit generally doesn't hang from the trunk of the tree. The fruit can only come from the growth points ("individual souls") at the tips of the branches. This fruit is grown by the whole tree through the twigs that will bear it.
It is quite common for individuals to incarnate with their soul groups repeatedly. This is not an hard and fast rule, however. The free will that is given as a gift of God provides us the ability to continually change our form in whatever way we see fit. So, some souls work well with their groups and others do not. Not every human incarnates with their soul group every time and neither case should be surprising. Sometimes what you really need is time to develop on your own. Other times, you need to be forced to face the incompatibilities in your self and your group.
Keeping in mind that every soul develops differently, it is possible that most of a soul group can choose to cut itself off from the tree, but a few twigs refuse to separate from it. In such a case, those who will stay a part of the tree can be spliced by the grounds-keeper onto another branch that is not separating. This allows those who choose to separate to have their freedom, but doesn't force every individual down the path of their group. This applies to soul mates as well. If the "other half of yourself" chooses to separate and you do not, then one of two things will happen (or first one, then the other). You may be sent (through incarnation) to try to "smack some sense" into this individual because you are the other half of that self. If it's obvious that the choice of separation will not change, then you will be separated from that whithering piece and given opportunity to find a more fruitful home.
Referring back to my previous post, these relationships are so powerful that they are potentially explosive. There is no one who can push your buttons like the other half of yourself. When two soul mates are exposed to one another in the Earth, they will clap together like magnets. This will lead to either turmoil then resolution or to turmoil then explosion. The same can be said for soul groups, though the effect is less intense. If two soul mates come together and are not developed well enough to handle the intensity, then one or both will react defensively. Don't we all know what happens in a relationship when you respond to intensity defensively? Boom.
From the perspective of consciousness, we are like atoms. The male corresponds to the proton and female to the electron. In this sense, positive and negative are polarity of charge, rather than desirable or undesirable behaviour. The two come together naturally to form one atom. The soul group would here represent a molecule of consciousness. Keep putting the groups together in bigger and bigger bundles and eventually you will have what might be called the "collective consciousness." As humans, we call this the "collective unconscious" because we are not directly aware of it. The fact is, however, that this invisible consciousness is more fundamental than what we think we are. What we think we are is an evaluation of emergent activity, rather than anything real or even material.
In the beginning (the creation of "individual souls"), every soul separated from God on its own path. This means that each of us has our own path to trace back to our true, singular origin; the One Source. This does not mean that we should "walk backward" or devolve into what we once were. Evolution always pushes forward according to the Will of One. It means that we must come to understand every step we have taken away from God in order to understand how we got where we are now. When we can fully understand ourselves and why we are where we are, then we will finally know our relationship to God and can be His companion (to be One with All). I would greatly enjoy jumping into quantum physics at this point, but I think this post is already long enough. Feel free to ask clarification for any of this.