Grey, I you are not happy, and sex is a deal breaker for you, then perhaps you should separate. Let her know that you tried talking to her about this, but her unwillingness to even discuss the subject of your M has caused you to feel so unhappy that you need a separation.
In a successful M you need communication, and you need to meet each others most important needs. If she cannot, or will not, do this, then you need to think about what you are really in here. Is it a M? Not by my definition. You are roommates that get along really well. Perhaps a separation is in order until she is willing to sit down with you and put some work into your M.
If your W continues to shut you out and not meet your needs, it is only a matter of time before you meet someone that will. Asking for a S while you give her a chance to meet your needs would spare her from that trauma.
