Title says it all. I'll give a short example, don't think of this as the only situation, apply whatever instance of controlling behavior you want.

Here's a classic: your girlfriend has regular girls' nights where she goes out to the club, bars, whatever. She says it'd be weird for you to tag along, because it's supposed to be a girls' night. She always ends up coming home late, drunk, and going straight to bed. She rarely answers your texts and when she does, she is annoyed/angry/dismissive. And to top it off, you'll sometimes see on her friend's social media that your gf and her friends are hanging out with a few guys you don't know. So much for "girls' night."

Obviously, you're not comfortable with the situation, and you're about sick of it. So what do you do? Tell her she can't keep doing girls' nights? That would be controlling, right? Is that okay? Why or why not? What are the alternatives?

It'd be nice if we could avoid the words "insecure" and "boundaries"

Edit: Again, this is just an example, don't think of this as the only situation, apply whatever instance of controlling behavior you want.

If you need some spark of inspiration, how about this: half of you who outright condemned the behavior of the guy in the example would probably think that your controlling parenting style is not only a good thing, but absolutely necessary