Oh I agree, and yes, having it feel less like a "self help" thing may help those who haven't gotten to that point of admitting it or recognising it (or may never get to that point). Nobody goes to a self-help app unless they are seeking self-help and kinda detracts from what might be what makes the app fun and you are right with other tools being patronising. Some I came across too went the whole "spiritual" route and I am far from spiritual.
Interestingly, one of the unexpected side effects of Pokemon Go was that for a number of people with social issues, it helped them, which for me outweighed the naysayers who were like "oh this is a terrible fad" or "how lame/sad", however, I didn't get into it myself, but our local animal shelter managed to raise lots of money just doing Pokemon Go nights. Come to think of it, on that note, I don't know if there could be some angle for events? But just a thought. But of course the Pokemon Go things is something that's mostly lasted with it being a fad and now less popular with people moving onto other things, though it still has a player base.
And I guess you're looking at using this app to define a social space for those more introverted and those who tend to struggle more socially. I can see how it can be a struggle to get the angle, you want it to be something that can help people with social issues, at the same time, keep the element of fun and not make it feel like it's a self-help thing. I don't know. But I like that you're taking a Sims-like angle to it at least.
However, I suspect you won't run into The Sims scenario where you lead somebody into an empty swimming pool, remove the ladder and watch them starve to death. One reason I guess I shouldn't be allowed to play, is that I am one of those people. I did it a long time ago with Zoo Tycoon I think? Made a lion pit and lured visitors to the park into it and then fenced them in. That was my favourite one.