It sounds to me like you've actually done quite a bit. You've traveled, learned to play two instruments, have a degree that sounds quite difficult to get, and you've been gainfully employed at a job that gives you a great deal of freedom. The issue is that you aren't satisfied with what you've done.
Until you said what your degree was, I wondered if I'd found my sister's Reddit account (which is to say that I know what it's like to grow up in a dysfunctional home environment). I also know that it's common to come out of that sort of environment in a different ways. Feeling unsure about what you want, fearing that it'll never be good enough, and just generally being withdrawn are all well within the realm of those reactions. It also sounds like you're socially isolated right now, which is definitely hard.
The good news is that you're already taking (or have taken) the first step: acknowledging that you want a change. Another tick in the good tally: you're willing to ask for help, which... uh... yours truly never does, both here and via therapy. But you aren't feeling satisfied or fulfilled, so how to address that? The solution is basically to change the way you feel about the situation, which can feel very 1984 to a lot of people, but isn't nearly as manipulative as all that especially if you're the one guiding the process.
I can honestly only tell you what has worked for me, and that's learning about both Childhood Emotional Neglect and Positive Psychology, and generally trying to understand about what the science had to say about overcoming adverse childhood experiences. A lot of people Positive Psychology because it seems too... "rose-coloured" I guess, but the techniques did work for me. (Highly recommend both this book and this series of MooCs if you're looking for some concrete resources). If CEN does sound like you, you can actually seek out a therapist who specializes in this kind of a thing, so that might help as well.
One thing you can try right now is "self empathy". Basically, many people are much harder on themselves than they are others, both in terms of expectations and what they tell themselves when those expectations are unmet. The gist is that you acknowledge and define what you're feeling, give your self some time to feel those things, but then consider what you would say to a friend or loved one who was experiencing the same thing. I doubt you'd call them a failure.
I'm not going to talk about "apples to oranges", because I personally believe that's just another kind of unhelpful competition. The aim is to be okay for you, not to turn your success story into some kind of personal myth. Acknowledge your challenges and use them as a stepping stone if you have to, but don't build your whole image of success on them, or else you're just going to have to face another crisis if/when you meet someone who's come from an objectively worse situation and achieved more than you have.