The flowers thing is alright for the friendzone angle. Just play stupid about it looked like she was having some tough time lately, but continue to pull in other guests to the place. If she calls you out on the flowers, then laugh about how dumb you can be at reading things but there's no need in addressing the issue. What I've learned painfully is that if they're not willing to talk then there's a stronger emotional component involved that's driven by body language. Forcing them to talk is a risk. It takes some effort to work that into a point where women will feel comfortable enough to talk what they feel. Not because they're evil and like playing games, but rather it's a defense mechanism they gradually pick up in their lives. Don't let her "time of the month" preoccupy you into changing your game or your attitude with the roommates. Women are more perceptive then men, so if you let up something is affecting you by their actions, more often than not, they'll use it against you. This observation is different in a long relationship, but this isn't one. This might seem like you're confusing her more, but just be who you are, don't act weird and let your actions force her into accepting the situation instead of you trying to bend over backwards to her confusion when you don't really want something long term with her. It could be that she likes the place too but doesn't want to ruin the long term aspects of it if a potential hookup goes sour. If everyone was talking maybe that understanding could be reached without really needing to say it, like "I really like hanging out with you two as friends. It helps me get my mind off of the other things outside the apartment..." Anyways, keep the gesture of trying, but roll off any lingering feelings of doubting yourself because that's the main thing that can sour the room situation fast. It's not really what you do, it's how you play it off.
Maybe you're reading too much into things OP. Stop tooting your own horn by thinking these girls want your D when they don't. That's beta. Bring whoever you want home with you and don't give a **** what they think.
Just a thought - is it possible that something totally unrelated to you was bothering her and it just happened to coincide time wise with your other hookup? Have you asked anyone else if they're receiving similarly cool treatment from her? It might have nothing to do with you at all.
To the OP, what is it you want out of this? You're sounding a bit consumed. What's good for the goose is good for the gander. You're doing things that committed couples do to try to figure out what's wrong in their relationship Unless you are trying to really hook up with her, just do your thing. If you want to keep the peace, don't do anything that they haven't done already. Be yourself, and if your roommate is not being extra friendly with you anymore, no big deal. You're not a mind reader. If something is bugging her, she should tell you. If you need to know, ask her. It sounds to me like you thought there was something there, and now you're getting the cold shoulder and are freaking out. Don't be the needy stalker. Relax, let it go. Just my 2 cents of course, and no offense intended.
your other roommate (the one on the right) is hotter, I say go for the threesome, but the left chick ain't worth the potential drama
Things have changed since I've lasted visited this thread; so here's what you should do now. Send her flowers again, and in the card apologize for sending her the first set of flowers. If that doesn't work, send a third set of flowers and in the card apologize for the previous ones and include a link to this thread also apologizing for starting it and posting her picture. If that still doesn't work, come back to this thread and request that a mod lock or merge the thread. Post it from your phone, screen capture it, and text the pic to her. If that doesn't work then just send her more flowers.
She's cute. But, I'm having trouble getting excited about that girl knowing she is currently on her period. OP, what you need to do is go catch a cockroach and let it lose in the living room while the girls are watch movies. When they see it and freak out, you can save the day and kill it. You can even put a Superman costume on under your clothes and rip your shirt off before killing the cockroach. You'll be a hero.
I would talk with her about the flowers and just say that it was just a friend thing, no expectations - just looked like she needed a pick me up. BTW - not a good idea, IMO. DD