He rejected me, indirectly, but still acts interested?

[raverae]

I told him I liked him, and asked him on a date. He told me we'd talk about it the next day (it was late when I messaged him). We spoke, just not about a date.

A few months later I'm invited to his party. I go. He's seeing someone, but I still noticed signs of interest;
Toes pointing towards me, as well as pelvic.
His girlfriend left to the store, and he stayed behind with me.
His did the eyebrow flash several times.
Hugged me several times ( to which she wasn't happy about.)
His tone changed with me, much softer and relaxed compared to with her. They bickered a few times and whispered a lot.
Noticed in pictures of us hugging, he has a dimple on his check when smiling. But he doesn't have a dimple when he's with her in any pictures.
He seemed to gravitate towards me a lot too.

Guess I'm confused. Why does he act interested in me, but with her could it be becuase they're having sex (they've only been dating for 3 months)?

[Sportjoy]

If he's into you, he'll tell you if he breaks up. Just don't wait and wait, just because he's attracted. Date other people, if they seem cool, and don't think it's cheating somehow just 'cause you have a crush on him.