Ah hell ride her til she bucks ya.

Give her what she wants, hit it and quit it. I wouldn't get involved with the girl any further than that.
And if the boyfriend shows up and wants to get physical and you know you can't take him legitimately fight dirty. Just do what my older brother taught me when I was growing up. If they can't see, breath or walk they can't fight. Poke the dude in the eye, kick him in the side of the knee or pop him right in the sternum. A fight is a fight there aren't any rules. It's always good to avoid it if it's possible but sometimes you just don't have a choice.
Or you could do the smart thing and not even talk to the girl anymore and not take my advice.

But if ya want to get a little mud for your turtle then I wouldn't blame ya.