Advice for dealing with an inferiority complex?

Hi. Sorry if this sounds awkward, I'm writing this off the top of my head and I have a tendency to ramble and run on a lot when I write/talk. 

I feel like I'm always inferior to everyone around me. I only got diagnosed about two years ago and I'm almost 22 but I still feel like a scared child! I can't work, I struggle to get out of bed most days, I don't leave the house more than three times a week, I'm anxious and childish and all my likes and interests feel like that of an 8 year old rather than a young adult woman. Meanwhile my twin sister isn't autistic, she's working a job, she has her own friends, she can travel, she does things that normal adults can do. My friends are all able to work or are studying, they can go out drinking and socialising and are functional! Compared to them, I'm useless! 

I've always compared myself to other people, me and my therapist agreed it's likely due to masking for so long without knowing, I would compare myself to others subconsciously to create my mask so no one would see me as different. But now that instinct to compare myself is killing my self esteem. I feel sad and inferior and childish all the time. It's driven me to do stupid things like refuse to allow myself to watch what I enjoy or budget obsessively because my brain goes "we're an adult now, and adults are RESPONSIBLE." and then I take it to the extreme because I don't know what else to do! 

I don't have any skills, I'm not in a state where I'm able to work, I don't have any mature hobbies or interests. Nothing about me is adult, and I always feel like the odd one out in my friend group because of it. 

I'm seeing my friends in two days and I'm worried. I just got through a really, really rough patch of inferiority and I'm worried that, as much as I love them and have missed them terribly, hearing what they're up to and watching them make plans to go out without me (because it's things I can't handle doing) is going to put me back in a rut. I love my friends, I truly do, but I feel so, so insecure about myself right now and I'm scared that seeing them will make it worse.