It's impossible to tell the "I'm an obsessive controlling person who wants my dh to think only of me" type, from the "I'm usually completely rational but something's got me worried and it's making me feel very insecure" type.
Hells yes.
It does sometimes emerge on threads as they progress though:
OP: AIBU to be worried? DH has gone to a work party.
MN: Ummm. On the face of it, no. Why are you worried?
OP: Because last time he went out a woman LOOKED at him. And SMILED.
MN: And what did he do?
OP: He looked uncomfortable and moved away! Obivious guilt!
MN: 
versus
OP: AIBU to be worried? DH has gone to a work party.
MN: Ummm. On the face of it, no. Why are you worried?
OP: Because he has a history of cheating on me with work colleagues and also of getting really drunk and claiming he wasn't responsible for anything he did whilst drunk and that I need to get off his case.
MN: YAdefNBU. LTB.
Situations/past experiences vary......