I get where you'd want to kind of use her since she cheated on you but honestly you are stooping to her level by knowingly screwing around with her knowing full well she has a boyfriend. You are better than that. Not to mention I'd be grossed out knowing she's sleeping with him too. Sloppy McFlopsalot.
PS I think you are already more attached than you think.
So, so you think you can tell Heaven from Hell,
blue skies from pain.
Can you tell a green field from a cold steel rail?
A smile from a veil?
Do you think you can tell?
And did they get you to trade your heroes for ghosts?
Hot ashes for trees?
Hot air for a cool breeze?
Cold comfort for change?
And did you exchange a walk on part in the war for a lead role in a cage?