How do i know my girlfriend doesnt like another guy?

[hmblms23]

there is a lot of things that u can look out for
if u know the specific guy, look at their body language
there is a show Lie To Me that will help with this, and although it is just a show, i have actually tried to carry what the characters use into real life just for fun, and it really works
if u want to use this to figure it out, go on hulu.com (it is a safe site) and search lie to me (if you dont trust me with this site, go to the website for the tv channel fox and go to lie to me full episodes
the episode "sacrifice" has a section where the main character decribes the characteristics of flirting
this involves tilting the head sideways and using excuses to break the personal space barrier, such as if he tells a joke, your girlfriend could laugh and softly touch his arm while at the same time moving closer to him. i hope this helps