Finding what you want out of life doesn't involve "thinking positive" It involves planning and work. The most positive thinker in the world can't do a thing if they don't plan and execute.
Take it one problem at a time and fix what can be fixed the easiest first so you get some self confidence. You feel fat and ugly so try to get some exercise into your day to make you healthier and not necessarily thinner...healthier is better anyhow. If you feel ugly, try some new hairstyles and make-up and ask others how you look, not yourself. You can't trust your own judgment right now.
You live in your parent's basement...so enjoy it and make it your space. My parents were both dead by the time I was 26 so I would have killed to be able to do that. Home is where YOU make it. So make it yours. You won't "always" be "living" under them for they aren't immortal. But it does give you the chance to save money for the place you do want.
You hate your jobs yet you probably sabotaged your job interview for the job you do want with the negative attitude. Sit down with friends and ask for REAL feedback on how you act and take the bad stuff they give you...you need to know how you are perceived so you can fix it. Real friends will tell you when you need to change and as their real friend, you won't hold it against them for telling you the truth. Once you know how you come off to others, you can change it and then go and re-apply for that dream job.
And everyone can have fun if you allow yourself to have it. Even a baby will have fun just looking at it's own toes. You have to figure out what is fun to you and then do it. Fun to me is being alone with my cats, hanging out in my yard and watching all the wildlife that comes to visit....from hummingbirds to black bears. And for real fun, I visit a zoo or an aquarium pr
a museum. But then I'm older than you. But I had to figure out what I liked to do by myself(and with others and then do it...and it changes with age).
I've spent the better part of my almost 59 years in therapy because I was abused within an inch of my life as a kid. I now battle major life threatening illnesses. And I'm very happy. And I've worked for every bit of that happiness. I've planned and thought and practiced and done whatever I had to do to get what I wanted and I'm not done. I will be working to find my own happiness until I take my last breath.
I once complained to my shrink that life wasn't fair. And he simply looked at me and said the word "fair" does not apply to life. He explained that we use the word fair to describe a "fair ball" in baseball or a "fair play" in football" or keeping your ball in the "fairway" in golf. "Fair" is a word that is used in games and life is not a game, therefore the word does not apply.
Cinderella is a fairy tale and fair does not apply to life. You get what you work for and that includes happiness. So start planning and trying and you'll get the hang of it slowly but surely and before you know it, you'll be a happy person doing what she wants, having fun with friends and maybe..living where she wants to. But it all takes time and lots of hard work. But it is so worth it!
If it can dig me out of suicidal depressions, it can work for you too. At least you have parents who love you and let you live at home. My mother died when I was 21 and I kid you not, my father sold the house, gave away everything inside including my personal belongings and moved, giving me no forwarding address or phone number. I could only reach him through his secretary. He just disappeared from my life 4 months after her death. Yet I survived and was happy.
You make your own happiness.