I've known this girl for a while but fell out of touch for a year and a bit and now she's started initiating conversation more - obvious interest and attraction and I'm playing it well, only problem is she has a boyfriend. Usually I wouldn't condone or take part is being a homewrecker but her boyfriend is a raging douchebag so I'm lacking any remorse or guilt here - I truly believe she'd be better off without him (dare I say, with me?).
Regardless, most of our interaction happens through text messages and I'm scraping along staying out of the friend zone, even when we do hang out I don't know what to do because I can't initiate anything/be overtly interested because then I'll be "that guy" who tried to break her and her "perfect relationship" up.
Shit has to be subtle and build attraction until she can't take it anymore but I'm worried I'll be thrown into the friend zone and she'll stay with her boyfriend and I'll just be aggrivated to fuck because I actually dig this girl.

Guys, how should I play this?