I'm a very similar character to you. I'm the same age and still would rather spend the day with my mum than with my mates. I'd much rather go on holiday with my parents than go on an 18-30's holiday with my girl mates.
I've just come to accept that I'm just not a social butterfly. Possibly it's to do with my childhood - being overshadowed by a sibling with a mental illness meant I spent a lot of time occupying myself and that's how I am as an adult.
Hmm, I think it's a case of just ignoring 'what's normal' and just be who you are and not give a damn. If you're happy being with your parents, then that's fine.
I would say though, that I do have one friend with whom I share a particular connection with - we read the same books and attend conventions together. It's the only time I can socialise and still feel like myself. Maybe you just need to meet some like minded people your own age you can do things with.
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