Adapted from a recent online discussion.
Trust boyfriend, female roomie but keep an eye on the situation
Q: My boyfriend of six months is looking for a new roommate, and has offered the room to a young woman who has just broken up with her boyfriend. I am a complete believer that men and women can be "just friends," and my boyfriend has earned my trust.
Yet I find myself already exhausted at the idea of keeping my own insecurities in check. I don't want to prejudge this woman or make my boyfriend feel like I don't trust him, so should I put the kibosh on my irrational worries unless something actually fishy goes on?
But your worries aren't entirely irrational. While I agree that men and women can be just friends, proximity is also a huge factor in bringing couples together ("The One" mythology notwithstanding). And, yes, Boyfriend can be happy with you and still fall for her.
That means you both need to be realistic: If there's any attraction between Boyfriend and Roommate, the rooming situation will fuel it.
Of course, there's no way for you to assert your interests here that won't open you up to paranoia charges. "Please don't tempt fate by having a female roommate"? "Please choose someone gross"? Requests like these put your date on the defensive, and leave you marveling at how low you'll stoop.
Please note that I'm not taking an "if it's meant to be…" position; there's definitely a place for thoughtful choices. It's just that, at the six-month mark, you and he are neither established enough to feel beholden to each other, nor new enough to go your separate ways without pain. So, I could argue that both courses of action are appropriate for him to take — choosing only male roommates out of consideration for you (because even couples who are great for each other need to be mindful of gratuitous temptation), or choosing any roommate he wants.
Given all that, I think your best bet is just to say, "I think there's an element of tempting fate with a female roommate, but objecting to it feels wrong, too," and let him figure things out from there. Or don't say anything and let the story play out. That puts us right back where we started, but that's not always the worst place to be.
Re: Boyfriend's new roommate
Anonymous: If he does choose this newly single woman to be his roommate, she could befriend her. Would pre-empt lots of potential problems, and she might make a great new friend in the process.
Carolyn: It makes a lot of sense, but also gives me the heebies, because it sounds a bit like fraud. If they get along when they meet, then she by all means should put in the effort to get to know New Roomie. Otherwise she'd just be feigning friendship for ulterior purposes. Meanwhile, if Boyfriend and New Roomie find each other attractive, then a friendship between Roomie and Girlfriend might slow their momentum, but it won't stop it.
Letting this sort itself out might be the only advice here, because that's what's going to happen, whether she tries to sway things in her favor or not.