I am looking for the right word(s) to describe a person who lies and invents stories/scenarios to elicit sympathy in order to manipulate and further their own advancement at the cost of others. Think along the lines of a psychopathic social climber, consumed by bitterness. Highly vindictive and vengeful due to an invented notion of unrequited love. Someone who has taken a twisted private fantasy and used it to try and gain both attention and allies against their perceived rival, regardless of that person's actual innocence. Thanks in advance for any input.
Such a person likely has Munchausen syndrome:
Munchausen syndrome is a factitious disorder wherein those affected feign disease, illness, or psychological trauma to draw attention, sympathy, or reassurance to themselves.
I don't think a single word could encapsulate all of that :)
The following words cover some of the behaviour you described:
Another idea might be "Ripleyesque" in reference to Tom Ripley a literary character who shares many of the characteristics you described.
fantasist (fæntəzɪst) /countable noun
- A fantasist is someone who constantly tells lies about their life and achievements in order to make them sound more exciting than they really are.
This term can also be used in reference to someone who is referring to tragedy to gain notoriety; see use in the article "The fantasist of 9/11: The story of Tania Head's escape from the Twin Towers captivated America and made her a heroine among survivors... Just one problem - she wasn't even there that day"
edit: My experience is that someone who exhibits this form of behavior is setting up a swindle of some kind. The goal is to be confident until people are confident in you in order to swindle. It fits the first definition of con artist. Synonymous is confidence man, and con is short for confidence as the goal of the confidence man is to exhibit an aura of confidence and trust around him on a venture which relies on trust.
noun Informal. a person adept at lying, cajolery, or glib self-serving talk. a person adept at swindling by means of confidence games; swindler.
The first part of your question --
a person who lies and invents stories/scenarios to elicit sympathy
-- sounds like a form of Munchausen Syndrome (as others have mentioned):
a factitious disorder wherein those affected feign disease, illness, or psychological trauma to draw attention, sympathy, or reassurance to themselves [Wikipedia]
The next bit,
in order to manipulate and further their own advancement at the cost of others
is well summarized when you use the term "psychopathic social climber". Finally, the rest of the elaborations in your post sound like hallmark traits of someone with narcissistic personality disorder:
a personality disorder characterized especially by an exaggerated sense of self-importance, persistent need for admiration, lack of empathy for others, excessive pride in achievements, and snobbish, disdainful, or patronizing attitudes [Merriam-Webster]
I believe one option you could consider is the word "histrionic." Histrionic, besides being a usable word by definition it is also associated with a clinical personality disorder and as such carries with it the connotation or at least begs the question of a diagnosis.
British Dictionary definitions for histrionic Expand histrionic /ˌhɪstrɪˈɒnɪk/ adjective 1. excessively dramatic, insincere, or artificial: histrionic gestures 2. (rare) dramatic noun 3. (pl) melodramatic displays of temperament 4. (rare) (pl, functioning as singular) dramatics
As already suggested in previous answers, 'narcissistic personality disorder', 'scheming' and 'manipulator' are most suitable for your case, but if the person uses unusually (deceptively) passive or indirect tactics, you might consider passive-aggressive personality:
passive–aggressive : being, marked by, or displaying behavior characterized by the expression of negative feelings, resentment, and aggression in an unassertive passive way
It is passive-aggressive behavior, the donning of a mask of amiability that conceals raw antagonism toward one's competitors, even one's friends. — Hilary De Vries
Passive-aggressive behavior is fundamentally deceptive aggression, where the inner resentment is cloaked by an outer pretence of placidity or neutrality and antagonism is expressed not through open hostility but through manipulative behavior (whuch can even include subtle lying, turning people against somebody, and feigning hurt or illness to elicit sympathy). It is not so easy for others to recognize or identify passive-aggressive behavior. Here "donning a mask of amiability that conceals raw antagonism" is possibly the part that fits your case.
As a single word description, I think you could use munchausenian. This is modified from Munchausen syndrome, as also mentioned in jwodder's answer.
I am unable to find it listed in a dictionary, but have seen it used as a descriptor for someone that has or appears to have Munchausen syndrome.
A link of examples of usage has been supplied by Mari-LouA, wordincontext.com/en/munchausenian
The last years of his life were spent at El Tovar, regaling the tourists with his colorful and imaginary incidents of the wild and woolly days. He was quite proud of his Munchausenian abilities.
Dama Margaret Smith - I Married a Ranger
I would refer to such a person as a pathological liar, though it may have a connotation that there is no actual motive involved, not even sympathy.