How to throw in the towel?

19F, UK, back again. Still no progress made, no friends, no goals, never dated, etc.
I've come crawling back so many times, been given paragraphs upon paragraphs worth of advice, yet I can't change. I just can't imagine myself doing it, trying to fit in or dressing up and getting ready for a date. It's not that I have no social skills or even that I'm too ugly because there are landwhales I know with all of these things, it's that I can't fathom not existing outside of most people's worlds - it's not right, and it's not me.
A large part of my unhappiness is that there is this false hope that keeps me trapped in this loop of 'it's so over' and 'we're so back', and I think it's time to let it go, hard as it may be. I wanted to be someone different and strived so hard to reach who I wanted to be, but, evidently, it doesn't align with who I am at my core. It saddens me but I'm never going to be a cute girl out with her friends in the day and on a date in the night, or even date at all.
I'm still young so I'm sure that I sound hasty, but I know that this is what's right for me. How can I let myself give up? I'm so tired of this.