Why are my friends so weirded out/concerned?

Ri

My bf and I have been together for a good 2 years. We are highschool sweethearts, both of us are 19 right now, but I turn 20 later this year. Anyway my bf and I have never had an argument. We have never yelled, are had a general fight about anything. We have only had one rough patch in the middle of our relationship that many of our friends are still shocked with got through with out us killing eachother.

Anytime we disagreed about something we have always been able to talk about it without a problem, we state our problem, and give our stance on i, say a sorry if it was deserved and moved on. Every time people ask us about how often we fight and we the them how we handle every thing they are confused, and sometimes even say that us getting along so well is a unhealthy thing.

He and I don't really understand why they think that way maybe you guys can explain it to us.