In Person

Body turned away from you
Has phone or other object out and engaged with it
Appears annoyed or bored with the current interaction
She shuts down intimate moments
She keeps her distance from you in an interaction
Direct eye contact is usually avoided
Her friends come and swarm you, usually involving her departure


Text and Phone

Responses are often short
Message response time ranges from very late to never
Emotion appears to be lacking in the conversation
You are always the one initiating the interactions
Phone cuts to voice mail after 4-6 rings (2 rings to connect, 2 for her to respond)
An offer to talk over phone is ignored with no response
Friend requests are ignored and rejected after a long length of time


General

She tells you that she is not ready for a relationship
She says she wants nothing serious
She gives you the "Let's Just Be Friends" speech
She curbs sexual escalation
She constantly seems to be busy when you ask to make plans
When plans are made, they are very vague and easily broken
Her former exes are openly discussed with you
Acts of chivalry and being a gentleman are rejected or shown no appreciation
She expresses her interest in your friends or other people
She tries to set you up with other people
She does not show genuine humor in your jokes
When she describes her ideal man, it is exactly not you
You've never been to her place
She is rude to you
She says she is taken with or without any proof
Mutual friends tell you that she is not interested
She manipulates and uses you for personal entertainment and higher gain
She invites her friends along to any plans that are made
She tells you what her friends think about you, and it is not good
Her friends and family have never heard about you after a long length of time
She doesn't freak out when you hit on her friend, or when you freeze her out