Jackie most def is Team Willcie! On the other hand, idk that she has a problem with stray guys, but esp now that Bill’s engaged, she might not like seeing him around?
That makes sense. Maybe Jackie was more okay with it before Bill was engaged? (Maybe still not totally pleased because he was totally seeing Mary Goodnight at the same time, but at least they weren't married or anything...) And now that he is, she's like: "Seriously Marcie. You can't keep doing this." So maybe Marcie made the concession of at least not bringing him 'round to their flat?
Though, tbqh, I feel like in general Marcie didn't bring him to their flat much anyway. Something to do with not wanting him to feel too comfortable in her space. Like she wouldn't let him even think about taking over the space that was hers and hers alone, because it'd be too close into letting him subconsciously think he could ever own her.
Which might be an interesting look into how Marcie sees Will as well, through the base fact that she DOES allow Will into her and Jackie's space, and even moreso that she lets him sleep over all the time. He might even have a small space in her closet like she might at his place.
Basically, Willcie is all but together, tbqh. They're just dumb and haven't actually, like... SAID anything to each other yet.