What are signs that your girlfriend is cheating and is flirting with other guys behind your back cheating?

If you know the person, you'll feel it right away. But here are a few more hints:

- doesn't answer the phone, leaves it off

- sharp rise in excuses for not answering, not meeting

- decline in sexual activities

- constant criticism on you, high propension to argue

- if she already has somebody in mind, talks about the person a little too often.

-Always says staying at a friends house.

- Late Home alot.

-Say's going out to dinner almost every night but never invites you.