What if you had a soul? Say you're a new soul, maybe just a baby soul. Now what if your soul didn't grow because of things you DID, but because of things that happened TO YOU. Like being born. You don't birth yourself, you get birthed. So that's the first experience that shapes your soul. Say you're going through life, stuff happens to you that you can't control. Happens all the time. So you react to those things as best you can, which sort of affects what sorts of things happen to you. Say you have a bad home life. You can't control that, it happens to you, so it affects your soul. You choose to react by running away from home (or something). This does not affect the growth of your soul, because you (and by extension, your soul) chose it yourself. But, this action does affect what things will happen to you because of it. You're a runaway, now you have to find a place to sleep; say you have to spend the night in the woods for a week or something. It happened to you, it affects you. Basically, your situation molds your soul, and you mold your situations. So it's like growing yourself by proxy, if that makes any sense.
Where heaven fits into all of this is here. Say you're old now. You've lived a long, full life, and you believe in Christianity. For instance. Say you die, still believing in God. Now, your soul creates this sort of pocket dimension bubble around itself, where it manifests its own afterlife. This is created by mixing what your soul expects, wants, and deserves. Since you were a Christian, you expect a Christian afterlife. You don't want to go to hell. You were a good person, so you deserve good things. So, you would get heaven as a sort of projection around yourself, as if you were playing a virtual reality video game about heaven, only it was designed by your subconscious (so to speak) to fit what you would expect there. However, since a soul is just a soul, there is no inherent deceitfulness in it. So you can't lie to yourself like you can in life. This is where the deserve part comes into play. Say you "go" to heaven and you like it and you percieve it as perfect, but it's not quite as good as it could be. Somewhere deep down inside, you would know that, but you could choose to ignore it for the time being and continue existing in the heaven you created. There could be anything in this heaven, including other people and even God, but they would all be just projections of what you wanted and expected. Of course, you would always know that everything you perceive isn't real, in the back of your mind. In the video game metaphor above, this would be like being able to play forever if you wanted and never having to stop for anything, but knowing you could if you chose to.
Now what, you ask, is outside of that pocket dimension? What happens if you choose to stop "playing the game" and decide to end that afterlife? Well it's like this. Say that, for whatever reason, your soul feels like it has been satisfied with this afterlife and "pops the bubble." Outside of this afterlife bubble is sort of a collective conscious of souls (think Karl Jung's collective unconscious here). This "soul soup" is an alternate dimension that runs parallel to our own dimension. This is a place where souls mingle and become one with each other, but do not lose their identity. It is a place of zen, where experiences are shared with every other soul, and there is no judgement. There is no such thing as a bad soul, even if you did bad things in life (things you do don't make your soul grow, remember?). Even if you did bad things in life, when you got to the river of souls, you would be able to reflect on that from every single different perspective of every other soul in that river. Since every soul is connected here, it doesn't make judgements. This is a place where everything is laid bare, and you can go, "Oh, I see where I thought that was justified before, and I see that it turned out badly, or could have gone better. I think I won't do that again." The feelings here are of peace, harmony, and contentment, since the connection between a soul and every other soul is strong, but not so strong that you lose all sense of individuality. Think of it as a place where every person is your friend, and you're happy just to enjoy their company, and when you talk to someone, everybody involved (being every soul) expresses empathy, kindness, curiosity, interest, and soothing approval for your actions, thoughts, or words, and you feel so good you pass it on to everyone else, and the cycle continues.
Now, you've probably met people who have been described as "Old Souls." These are souls who, for whatever reason, have decided to leave the river of souls and try again at life on Earth (or wherever else they choose. I mean, who's to say Earth is the only place life--and souls--exist?). They would go through the process of soul growth again, except that the soul would still remember its past life. You might not, but your soul would. It would add the experiences in this second life to the ones in its first life and do the afterlife all over again. Maybe in this life, the person is a Buddhist, so they create a pocket dimension that's a second Earth where they've been reincarnated into another thing. Maybe they believe something completely off the beaten path and they are the leader of a race of werewolves. It could literally be anything, and in each situation, the soul could decide when to leave that afterlife bubble and return to the river and share every experience they've had, again. This can go on as long as the soul feels like, until the soul gets very, very old. When this happens, a soul might choose to stop its existence altogether, if it felt like. This is a completely voluntary process, and completely painless. The river of souls retains that soul's experiences after it leaves. When a soul "dies," it's not really dead and gone forever, it's more like hitting a reset button. The soul that has chosen to end itself dissapates into pure energy, which is all around everything, everywhere (this type of energy being the scientific kind of energy, that makes things hot or move or whatever), and may coagulate back into a new soul after a while. So souls power everything: electricity, heat, however you have energy, a dissapated soul is doing that. However, a dissapated soul retains no experiences of its own, since it has dissolved its own consciousness (which is now being used in other ways). A soul can coagulate out of the ambient energy (maybe dark matter, wouldn't that be an odd way to tie this weird theory to science), but without any experiences. A "baby soul," if you will, that now goes through the entire process as a completely new individual soul all over again. The discovery of the soul river, the creation of its first afterlife, are all new to this soul. And it happens over and over.
