I'm choosing the negative path.

[third-density-being]

You are not Serving Self. You are hurt, resentful and trapped. You are maintaining vision of negative picture of Self in other-selves eyes and adopting it as Self-picture – or at least convincing Self that’s what You are.

You wrote:

It is legal, but unethical from my perspective

“Unethical”? Sir, You are a Positive Being whom have experienced too many negativity from others to process it properly without being bound/tied-down by it. I relate, as I’m in similar situation. Except I know I am positive but I consciously withholding Self from others.
“Making a decision” won’t change this:

It feels dark and cold and scary…

I don’t know why, but every time I’m contemplating eighteen Arcanum – “Experience of the Spirit” – I feel there’s something attractive on the negative path. Knowledge, mystery, ability, freedom unobtainable on the positive patch. But I do realize I cannot walk negative path, as I would not do what is necessary to prevail. Why? It’s simply – I do not draw energy from hurting others, from depriving them of things they need most, from controlling or forcing them into submission.
This is for me a “negative path” – when One is able to draw energy from such demeanor and welcomes it with excitement and joy/pleasure.
From what You wrote, You are convinced that You are unable to walk positive path and therefore You’ll take “the only other path available” – negative one.  

There’s always another way. Learn to care less about others and focus more on Self. Not “against” others, but FOR Self. Also, don’t bother Self with labels – STS, STO… drop it. Do not define Self by such duality. There’s no need for it and in doing so You’re narrowing your point-of-view. Get well acquainted with shades of gray and try to see that no-One is only “good” or “bad”.

Above is of course only my opinion and I have to write that currently I’m mastering “art of isolation”. I refuse to care for others and when I do, despite my efforts, I refuse showing / acting on it. Not wanting to be hurt or rejected is far stronger than need to be loved and accepted. I wonder if it’s the same in your case.