Girlfriend staying out all night with her friend?

My girlfriend of a year has a good friend from work that came to visit from out of town. Backstory her friend and her husband are essentially in an open relationship. They went out to eat with my girlfriend and legit I didn't hear from her until like 3 in the morning. She then told me she was going to sleep at their air b and b. They also took their kids with them so I don't know if this is like a club situation or just them going out and catching up. Am i crazy for being worried my girlfriend spent the night over there?

Girlfriend staying out all night with her friend?
Post Opinion