Doing whatever makes you happy regardless of what others think is what makes your dad an adult.
Your friends are thinking of it like kids, where you don't want to be perceived as younger than you actually are because being an older kid or teen is 'cool'.
But as you get older the differences start to flatten and ideally you start acting like 'you' rather than like 'your age' or whatever external criteria.
Hmm... I don't know how to explain it but I could DM you their website. It's less clinical, we don't talk about my diagnosis or stuff like that. Instead... You just talk until you start saying stuff you didn't know you wanted to say, if they makes sense. More questions less answers.
Edit: they have a pay what you can system, just so you know. It goes down to 0 lol
Doing whatever makes you happy regardless of what others think is what makes your dad an adult.
Your friends are thinking of it like kids, where you don't want to be perceived as younger than you actually are because being an older kid or teen is 'cool'.
But as you get older the differences start to flatten and ideally you start acting like 'you' rather than like 'your age' or whatever external criteria.