This is the hardest and most important question in anxious attachment, because the honest answer is: sometimes it is the pattern, and sometimes it is real information. Learning to tell them apart is the whole skill.
Short answer: an anxious feeling can be a false alarm, and it can be an accurate read of something real. The way to tell the difference is to look past the single moment at the wider pattern — repeated behaviour, consistency over time, and context — rather than deciding from one text or one off evening.
Anxious attachment can make ordinary uncertainty feel urgent, which means the feeling of alarm is not, by itself, reliable evidence about the relationship. But that cuts both ways. The pattern can produce false alarms — fear firing on a small, harmless trigger — and it can also be right, because anxious people are often highly attuned and sometimes notice a genuine inconsistency early. The feeling tells you that you are on alert. The why comes from looking at what actually keeps happening.
An anxious feeling can be old learning firing on a small trigger, and it can be an early, accurate read of a real inconsistency. Being told you are "overthinking" settles nothing either way — sometimes that label is used to wave away a real concern. A single feeling, however strong, is a prompt to look rather than a conclusion. What settles it, over time, is the pattern: does the behaviour you are worried about repeat, and is it part of a wider inconsistency, or was it a one-off in an otherwise reliable relationship?
Ask whether you are reacting to a pattern or a moment. One late reply is a moment. A steady, repeated pattern of disappearing, mixed signals or unkept promises is information. Anchoring to repeated behaviour rather than isolated incidents is the single most useful move — and it is the idea the book develops in depth (it calls the tool the Trigger-or-Truth Test), and it leaves both answers open until the pattern speaks.
If the pattern includes repeated dishonesty, controlling behaviour, contempt, or anything that makes you feel unsafe, that is not a question of your attachment style. That is information about the relationship, and it deserves to be taken seriously however you are attached. Safety comes before any framework.
Go deeper
The Anxious Attached is built around exactly this question — separating an old fear from a real relationship signal — with practical tools and 120 real questions answered.