Why Possession is More Common Than You'd Think
I'm not talking about possession in The Exorcist kind of 'crab-walking on the ceiling' sort of way. I'm not talking about possession as 'completely losing your mind, time and starting to say 'I'M SATAN'' over and over again either. But the sort of spiritual possession where you pick up hitchhikers; other spirits, people, living people, dead people, etc. over your lifetime. You can still function, but probably not as healthily as you'd like. Most people, yup - most - have had at least some soul part of them which isn't actually their own, at some stage. And this is because most people, at some point, have experienced some form of soul fragmentation.
Nature abhors a vacuum, and the soul is something that seeks to be complete and whole. It is an innovative, creative part of who we are, and it will use anything to spackle / polyfill any gaps or spaces within us. It will try and grab back the part that split off (which is why, over time, many fragmentations will self-heal), or it will be open to invasion from other energies, entities and people.
I don't really like using machine metaphors to explain something organic, but it's the only one I can think of right now. Imagine, if your soul was an engine (with artificial intelligence, lol) and lost some of its parts. The soul is innately aware that it needs those parts to create energy, wholeness, health, growth, etc. And like any good, creative mechanic, it will try anything, because that's what problem-solving is all about.
However, a broken engine is also fragile, and not always able to protect itself. Any entities or energies, or spirits or dead folk, can come in and masquerade as those parts creating an engine that poorly functions - often resulting in illness, a feeling of inner discordance, or a poorly sustained ability to not only manufacture energy, but to use it in a healthier manner. In worst case scenarious, flat out malicious energies can zoom into the spaces left behind by fragmentation, attach, and then systematically start destroying the rest of the engine.
Different energies are attracted to filling 'spaces' left in the soul, and here's a quick, and by no means exhaustive, list:
People you know: Yeah, it's true. If you've ever had a really needy or clingy relationship with someone, and find it hard to 'let go' of them (crushes are an excellent example here), chances are you've left part of yourself inside or around them. And in that space, chances are high that you've taken some of their energy (with or without their permission, it's usually a very unconscious and desperate exchange) into yourself.
Folks with really dysfunctional relationships with their parents, old highschool friends, abusive relationships, really co-dependent relationships etc. often find themselves in this position (in fact, co-dependence in my personal animistic practice is explained by each having way too much of the other person's soul within themselves - hence, they need each other, because the souls are convinced they do). The soul is, very simply, attracted to itself. If part of it is in another person, it will be hugely attracted to that other person, even if you know that it's not healthy / try to convince yourself that you hate said person etc. This is the most common form of possession, and ironically - can be one of the hardest to heal. I can flat out tell you right now that I am in this position myself, and I am not yet in a position of enough power to resolve it. It will simply take time.
People you don't know, who are dead: Ghosts, or spirits of the dead, who have not yet passed on and found their purpose in death (a big difference between a ghost and an ancestor after all), often seek to re-experience life and are attracted to occupying people who aren't whole or sound within their own soul. It's usually not a malicious act, but one based in need, loss, fear, and wanting to establish a connection with someone.
If they aren't malicious or destructive at heart, ghosts will innately know that what they're doing isn't really working for them, and can be easier to extract than the pieces of other people, or other spirits/energies. They are often welcome to suggestions as to what to do next, and if shown the way (by the self, a shamanist, or anyone who has good instincts in this area) they will take it.
If the spirit of the dead is malicious or destructive, the process can be fraught with more difficulty and resistance. You can't reason with everything, and in those cases, sheer oomph and sometimes a lot of help is what is needed to get the part out, and away.
Spirits: All kinds of spirits (I'm talking in the wight / demon kind of sense here, not in the vodka sense) seek to occupy folk for varying reasons. Because it's fun. Because they are mischeivous (kitsune come to mind here). Because they have nothing better to do. Because they are spirits and their motives don't need to make sense to us. Because they are actually malicious and simply enjoy destroying the spirits of others (ouch, true). Because for some reason we pissed them off and they decided to get even. Because they think they need to occupy us for some reason. Because they want to.
I have thought, in the past, that some cases of otherkin are actually forms of spirit/wight possession which have become more symbiotic and constructive; than parasitic and destructive. In Indigenous forms of shamanism, certainly some cases of otherkin would be treated as an illness, or at the very least an anomaly, instead of 'the way things should be.' It would also go some way to explaining why some forms of 'kin are more prevalent than others; because some wights are far more excited about the prospect of long-term possession than others (kitsune, fae, elves, pixies immediately come to mind).
Anyway, healing spirit possession is a wildcard in terms of how it will go. It depends on the wight and its strength, it depends on how malicious the wight is, it depends on how attached the soul is to that spirit, and it depends on how strong the shaman/spiritual healer is, and how strong their alliances are that could possibly help.
The most difficult extraction I've ever witnessed was a kitsune-possession (and it wasn't nearly as cute or sweet as all those DeviantArt illustrations make them out to be). But in this case, the person was literally possessed in that 'I have no sense of my own identity and I will growl at you viciously and then alternatively try and seduce you' sort of way. It wasn't a case of a person going 'hi, I'm John, I'm mostly sound of body and mind, except I think I have something inside me and I want it gone.' I should perhaps mention that if your client is really sentient and self-aware, the extraction is going to go much easier than if your client is pretty much being puppetted by the wight or spirit.
Because the soul (and nature, apparently) abhors a vacuum, it will automatically start seeking or 'calling' for replacement pieces once an extraction has been performed. Some neoshamanists will actually do a retrieval at the same time, but others will use energy or the person's own spirit guides or gods, to protect that space so that the soul can continue on its journey to find the rest of itself and locate inner wholeness. Other neoshamanists will pack the spaces with energy 'glue' or filler, or actually ask a spirit guide or helper if they are willing to live in that space until what is meant to be there returns.
As the soul naturally looks to replace any spaces with soul parts, or energy, any spaces within the self after an extraction are exceptionally vulnerable to simply being replaced by something else. This is why conscious self-extractions are often failures. Just like soul retrieval shouldn't be performed alone, soul extraction or possession resolution, or whatever you want to call it... probably is best with someone else to help, and add their energy to the procedure.
The good news is that in most cases, extraction is not actually an impossible or really difficult situation that puts your life in jeopardy and requires the making of a blockbuster film to illustrate (in other words, no, you will NOT be the next Exorcism of Emily Rose). Varying degrees of 'my soul is occupied by some stuff that isn't my soul' exists for most people, who go about their day to day lives without caring or really noticing. They may feel they aren't functioning at a rate they want, or may from time to time, be affected by it, but for the most part it doesn't affect them. The soul is highly highly adaptive, and in many cases, even if a form of possession is going on, the soul will be making it work however it can.