SO vs. Boyfriend ?

What is the real difference between these two terms ?
SO is overused 
Earlier today I saw a teen referring to her "boyfriend?" as SO and I was like WTF?
In my head I was like you  have been on 2 dates and he is your SO ?
To me a person is not your SO until there is a stable relationship, 
It's not when you are like just dating and seeing if things will go somewhere
Some of y'll might comment rudely by saying it's none of my business 
I agree 
It is none of business 
I just want to know 
Hence posted in Contraversey corner