Everything you have said points to high Fe and you're not Ni PoLR. There's nothing in your posts that strike me as Te or Ti.
- I am very realistic
In Socionics, EIE is considered negativist in the positivist/negativist dichotomy. And no, not all NFs are optimistic... You may have a wrong impression of NFs.
- My IxFx family members have referred to me as "nasty" and "horrible"
SEI, ISFp, is the supervisor of EIE, they can often disapprove of EIEs. Contrary (EII, INFj) or illusionary (ESI, ISFj) aren't guaranteed frictionless... Especially contrary can be difficult. As a rule of thumb I don't get along with Fi users beyond a point. Mirror relationship (IEI, INFp) are easier.
- I have been labelled by people as "narcissistic", "histrionic" and "sociopathic"
This is just a label, and it does not define you. People who are actually narcissistic and sociopathic don't admit they are. As long as you don't have a diagnosis, these opinions are irrelevant. But it does give me the impression that you are able to wear masks easily, which is a trait associated with EIEs. It's a powerful trait, one to be admired.
Things that point to beta values:
- I'm pretty blunt and I tell it as it is
- My friends have said they admire how I do not let anyone walk all over me
- I hate incompetency
- I can be quite tactical and strategic- I enjoy chess for this reason
- I am very realistic (NF types sometimes interpret this as pessimism)
- I don't like people who can't take a joke
- I like being controversial
- At times I am guilty of "black and white thinking"
- I have always been popular at school - I'm the queen bee/ the Regina George.
- I am often the first to take action in a situation, I'm not one to sit around and moan if I have made no attempt to solve the issue
- I am a natural leader, I am able to organise people and be like "you do this, you do that"
- Ideally, I'd like to go into a career in journalism - preferably online
- I will break rules to get what I want
Betas embody the spirit of rebellion. They are system creaters. They give zero shits about existing social norms and have no problems breaking them to get what they want. They are catalysts for social change. EIE is the heart and soul of the Beta Quadrant, EIE is the absolute monarch. Decisive and merry is written all over you. You are one tough person indeed!
The biggest piece of evidence:
"One recurring dream/vision I have is of a new world, unlike this one. Being logical and ruthless is seen as the best traits, being emotional gets you left behind. Of course, I am the ruler of this world and everyone fears and obeys me. They all wish they could be me. I marry a guy, for money. He is like a piggy bank to me, he doesn't own anything, all of his things go straight to me."
No Gamma will ever say this. Gamma is too Democratic. This is aristocratic through and through. Your vision of a new world, where social laws are rewritten and people follow your ideals, this is Beta. If Beta has one message it is "Fuck the system!" EIE is logical and ruthless, no questions about that. They're not a "soft" type. Beta types, all of, them experience violent passionate emotions. Like the quotes in my siggy... That's beta love. EIEs can generate such feelings and the activator and dual enjoy them. You being the ruler, being a social leader, is not something gammas aim for... No other quadra has visions like that. Marrying a guy for his money - wealth and power are related to Se... You may be talking about your dual here... LSI?
Rest of the stuff isn't really type related.