Seriously. I know a lot of ISFJs. Five, to be exact.
Three are female, two male. Two out of the three females are extremely, extremely emotional. The two males worry SO MUCH, and the remaining female.. She is fairly stable when it comes to emotions. But the two other females? OH GOD. They're ungodly emotional. Touchy, cry a lot, easily offended, easily upset. I really, really dislike it sometimes. How can anyone be so emotional?
For example, my ISFJ friend (one of the two females) slept over last night. In the morning, she got an upsetting call, and she started BAWLING. When she hung up, she told me the reason, and I almost face-palmed. She did have reason to be upset, but it was NOTHING to cry about.
I'm wondering if they're not unhealthy ISFJs?
In my opinion, a healthy ISFJ should be emotionally stable, very quiet and behind the scenes, very concerned about the well-being of the world around them.