We tend to have this very narrow idea of success. Like, if I say "success" you probably immediately think career, wealth, fame. Those are definitely things to be proud of, but there are a lot of other successes that I think are ultimately more rewarding. Like the successes of relationships and experience and community and purpose and fun. But if you have this narrow idea of success and then achieve it but aren't fulfilled it must feel awful. You probably feel crazy, like "I have all the stuff of happiness and yet I'm still sad. I must be broken." Meanwhile you have people telling you how ungrateful you are, and you feel ungrateful, so you suck it up and put on your fake face and hope no one notices how bad you are at life.
But its OK! You're young and driven and smart so this is totally fixable for you. You've even identified the problems already: you need to change your relationship with your parents, you hate your job, and you need more social interaction. All totally normal human problems. Let's see what we can do about them.
The Parents:
Our parents have this idea of us as children and they try to hold on to it as long as possible. We then have to break this idea and make them see us as adults. Its important that we do this because as long as they see us as children we can't have a real relationship with them. They're interacting with the child we no longer are and we're playing a character for them. Usually this happens during our rebellious teenage years, but it doesn't have to. You might be able to do it just by making them see that you're sad. Your parents obviously want what's best for you, so if you can make them see that the plan they had for you isn't working not only will it help gain their support for the changes you're about to make, they'll also have to rethink who you are. Regardless of how you do it, its going to be pretty uncomfortable. But finally getting to interact with your parents as equals and friends is really rewarding.
The Job:
I also had parents that pushed me very hard academically, but they were sort of jerks and I hated it so I left. They basically wanted me to take the path you took, but I couldn't see myself being happy that way. Plus they were miserable so how good could their advice have been? So I dropped out and tried to make it as a musician. I never made it, but it was totally worth it. I got to spend my twenties doing something I loved with great friends and I got to tour a little which is the best. And even though I'm not the greatest musician in the world, I got to make something I was proud of, that mattered to me. These days I want to find something else to do, but you know what? I didn't miss out on anything. All my opportunities are still there. I could go back to school or learn a trade, I might travel a while and write or just climb things. You have your degree, you can totally do something "silly and childish" for as long as you like and still go back to your career. You might not still make 100k, but you might be happier. Or you could work your ass off and retire early, or work part time. Sometimes it doesn't even matter what it is you're doing. As long as its new and scary it will allow you to change and grow which is always rewarding. Point is, you have lots of options and none of them are likely to ruin your life in some way that could never be fixed.
Social Interaction:
First off, you should definitely be penpals with Beareavershark. That guy seems rad. And yeah, call your sister. Breakups are this weird time when you need to hang out with people but you know that you suck to be around so you try not to bother anyone. I'm sure she would love to hang out with you. Then go make a friend. We always think we're going to hate talking to strangers, but usually it ends up making us happier.
tl;dr: You're doing a great job and you should be proud of the successes you've achieved. But you also know there are problems in your life and you know that if you break them down into achievable goals (call sister, make a friend, etc.) and work towards them you'll be happier, so do that.