OK this is just my experience:
When you first meet a girl, if you look into her eyes and she averts after a few seconds by staring down, she is showing submissive behavior and thus translates into IOI. This is usually accompanied by some other IOI soon after, such as touching her hair with her hand. If she looks to the side, that is a weaker IOI. If she rolls her eyes, that is an IOD
But if she keeps looking into your eyes and smiles, huge IOI.
But if you are in comfort building, and you look into her eyes like before...and she averts your gaze after a second or two, it's either because you're making her nervous or because you're losing her interest. Here, it translates into IOD. Girls have an incredible capacity for staring into your eyes when they feel a connection to you, and you definitely don't want to lose good eye contact later in the sarge.
Rodeo, let me just add that you shouldn't be cheating on your wife and 8 year old kid like this. Call me old fashioned, but the idea of your son (or daughter) finding out you are gaming behind his mother's back disgusts me. And I'm not talking about playing the wii.