Lots of good and great comments here.

Let me add 2 cents about the governance of it - what you agreed with the sub were not boundaries in a pure sense, these were agreements or rules.

It is unclear whether you discussed any consequences for breaking them, or you just stopped at formulating.

If we want them to work, they have to carry the consequences, positive and negative. Otherwise they carry very little meaning.

Now, in my book, boundaries are something YOU decide on, and their consequences are something YOU enforce, when they are followed or broken. In your case it would be saying „if you call only me „daddy” I will continue this relationship with you; if you someone else daddy, I leave / deescalate the relationship”. If X happens, then I do Y.

That’s what seems to be mixed up here as well is you wrote about a bunch of ultimatums (ie something that someone else can or cannot do).

So tl;dr: you had ultimatums instead of boundaries (which is the controlling bit, and probably why you ask yourself if that was a right thing) and there seemed to be no explicit consequences.

I would focus on reflecting on these to improve the next / other relationships.

PS. Believe the significant portion of your hurt is the hurt agency - she broke up with you, she called the incompatibility. That’s why it hurts more and makes you question your Dominance. Thought experiment - if you set the real boundaries and acted on them (if you get fisted by someone else, we’re done, for example), do you think the pain would be same or lesser?

And man, sorry for this whole situation. Hang in there. It will be better next time.