Dating or living apart together?

Bf and I have been together for 4 years. I have 3 older kids that live with me. He lives about 45 minutes away and has his son every other weekend. I go there on kid free weekends and we get together as group when he has his kid.

He has been married twice and me once. We have made comments about not going anywhere, forever people, and in it for the long haul. I don't think we will ever get married though.

We are both introverted and have our day to day things. He is an engineer and I am a teacher.

He recently decided to buy a home and get out of his apartment. I went through a rejection thing because he didn't want to move in with me. I have an adult child with a disability and his future is unknown right now. It took some processing to accept his decision.

He has put me as beneficiary on some of his accounts so that's pretty big I guess.

My long rambling question is at what point is the difference between dating and living apart together?