Should I go for this girl?

Ok, so my mate was after this girl for ages but he gets Nervous as, this is my best mate.

So me being a wingman manage to land him 3 dates (the third today), and for whatever reason I was invited along.

However I get, our friendship group get and my mate get the idea that this girl likes me more than him and my mate is pissed. She always texts me and sends me pictures of her and calls me and stuff but not him.

I'm stuck between getting this girl i.e. having someone, and dogging my mate, or I can stick with my mate and lose this opportunity because she doesn't really like him (so I've heard from one of her friends).

There is a lot more to this story in terms of detail but I'll just make this brief. I am interested in this girl especially because I just got out of a relationship not long ago. So I would like some advice.

Should I back off or go forward

Thanks