First, let’s sort out the idea that depression and anxiety are not illnesses or diseases. Depression and anxiety are not the same as major depressive disorder and generalized anxiety disorder. The distinction is important because the latter are psychiatric illnesses, that is, permanent conditions you can’t cure, and which tend to be for life (although they are not always permanent).
Generalized anxiety disorder has symptoms that manifest on and off, usually on a daily basis, and the symptoms are usually triggered by situations. The person who is calm at home but gets really nervous as soon as they are around people is a good example. Depending on its severity, people tend to take medication for this every day, and therapy also helps although it tends to not be sufficient.
Major depressive disorder has symptoms that come and go, in a seemingly random fashion, although they can be triggered by life events or particularly bad periods of life; the person has depression on and off, usually for prolonged periods of months or even years, and they feel just like everyone in-between bouts of depression. Usually, during periods of depression, people with this disorder take medication, and they stop medication when the depressive episode is over, although some manage without medication and that’s okay too. Therapy is used to prevent episodes, hasten recovery from episodes and to reduce distress and suffering during episodes.
Depression and anxiety are a normal part of human experience and everybody lives through them sooner or later. For example, who hasn’t been nervous during an exam? That’s anxiety. Who hasn’t been under the weather for a month after a breakup? That’s depression. Being nervous or sad are simply emotions, not diseases. In both cases, since the situation is temporary and is not a disease, and since these are very brief periods and don’t tend to cause a chemical imbalance, no medication is required unless the case is extreme. A woman participating in a beauty pageant can suffer from extreme anxiety for only the few weeks leading up to the Big Day, and she might need medication during that time. A man whose wife died suddenly in a car accident might only have depression for a few months but it might be so severe he might benefit from taking medication during that period. Yet we are still not in disease territory and usually they only need to see their family doctor and not a psychiatrist. Psychiatrists are best called upon only after referral by a family doctor or a psychologist, in cases of possible severe and chronic mental illness. Psychiatrists are rarely the first line of care, and that’s as it should be. The rare exception is things like psychosis.
Now, let’s sort out the difference between manipulative and manipulation.
Manipulation is the act of manipulating. No adult, or even child for that matter, can honestly pretend they have never manipulated or at least tried to manipulate. Who has never lied to achieve some goal? Who has never cheated on a test or not disclosed information they were asked to disclose (hello, people with perfect, shining resumes)?
Manipulativeness, on the other hand, is a personality trait. It tends to be permanent, which isn’t to say manipulative people always manipulate, but the tendency is always there and they manipulate fairly often, sometimes even without realizing that they do (it becomes second nature if you do it often). The fact that a person is manipulative doesn’t mean they have a mental illness, even though many a mental illness has this as one of its diagnostic criteria.
Now, for the concept of normalcy. Normal is said of something that is widespread and generally accepted. What is normal isn’t necessarily good, or better than another thing that is not normal. I am an example: I have Asperger’s syndrome, and although I am part of a minority, I have a higher IQ, I am more honest and I am less superficial than the majority. Thus, I am not normal (except among other aspies) but I am, at least in these regards, better than those who are normal. Of course, there are things at which I am worse than “normal” people, and no matter how much I am being harassed to be normal or at least to seem normal, I can’t. Sorry. My point is, unfortunately, the word normal only refers to what is habitual and accepted. I am not normal, therefore, I am not accepted. Such is life.
Unfortunately, nowadays, we allow selected individuals to decide for the rest of us what is or should be normal. An example of this is the DSM. For example, because the DSM says it is not normal to have issues expressing empathy (even when you have just as much empathy as “normal” people and only have difficulty expressing it as expected), all those who have these issues are seen as not normal. And as soon as the DSM says that this is not normal, it creates an expectation that I either become normal (I can’t, try as I might) or that my ideas and feelings are not as valid as those of “normal” people simply because I am not “normal,” thus they are of little consequence and should be excluded of the fabric of society. It also creates the expectation that, in case of conflict, I should be on the losing end because I am not “normal,” independent of how valid my argument is and how invalid my opponent’s argument is. They are normal, I am not, they win, I lose, end of story.
Is it normal for someone to have anxiety and/or depression? I (and many others, including many “normal” people) say it is. Luckily, the DSM has nothing to say to this. Depression and anxiety are not in the DSM, and I hope they will never be. Is it normal for someone to manipulate others? While it is not necessarily productive behaviour, it is. Is it normal that someone is manipulative? Depending on their life experience, it might be. If your plane had crash landed and you developed a phobia of flying as a result, it would be normal for you to have that phobia, even if it is not a “normal” state of being in the general population.
Is it normal for a person who has anxiety and/or depression to manipulate? They might have fears and worries in that moment they don’t usually have, and fear and worry push many people to behave in ways they usually wouldn’t. So, while that person may know their behaviour is not “normal” and even feel bad about it, it might seem to be their only option in that moment. But that doesn’t mean that that person is manipulative. If that person gets the help and support of their loved ones, and perhaps extra support from their community and maybe from a doctor, a psychologist or a psychiatrist if need be, the manipulation might never become manipulativeness. If that person doesn’t get the help and support they need, or if it takes years before they do, that’s a different story. In my book, not getting the support and help needed would not be “normal.” But even if that might happen and make it difficult or unpleasant to have a relationship with that person, you can’t blame them for it. No one deliberately chooses to be that way.