Context of a swedish phrase. Hjälp!

Hi everyone!

I'm learning swedish and I'm also interested in understanding the culture of Sweden because I've been dating a swede for a while.
So, my question is, when do swedish men start referring to you as "his woman" or "min kvinna" as they say in swedish? I mean, they say so in just any type of relationship? I'm a little confused 'cause in Spanish (which is my native language) when guys say "mi mujer" it means they are already married, but since we're not, I want to know when they start talking about you like that.  Is it when the relationship has got serious to them? It kind of hit me when he said it the first time.

Hoppas att någon svarar på min fråga snart. Jag verkligen behöver att förstå och det kännas inte rätt att fråga honom om det.
Tack på förhand!

Kenia