i feel bad for the OP because i've been in a similar situation to what he's dealing with. basically OP, you need to start planning ur exit now. in your case, u just cant call her up and break up with her. u live together. its better if u either find another place to leave, and when u do, dip on her and let her know its over.
the point is, this girl has gotten way too comfortable. and i get that u may be emotionally attached to her, but for ur own sanity, and to make sure this does not affect ur job, u need to get another girl on the side asap.
life is funny at times. never in my life did i ever deal with a girl that didn't want to have sex or didnt' give up sex when i wanted. when i dealt with this particular girl who did just that, every voice in me told me to dead it. and granted, i deaded it a few times but shed call and we'd make up. she had her own issues (was molested as a kid, her biological father didn't care about her, her mother is screwed up in the head), notwithstanding, these were not enough reasons for her to deny sex.
i say life is funny because, when things finally ended, the girl i dated after her was a nympho who wanted nothing more than to fucck fucck fucck. so much that it freaked me out and i kinda lost interest in her (a lesson to others that u shouldn't let people know how much u want something). this new girl basically told me "i dont need u to take me out to eat or any of that stuff, all i want is d1ck d1ck d1ck" lol. its really funny yall. that helped me restore my confidence.
to OP, kinda like how its easy to look for another job IF u already have a job. while u have this girl in ur house, start looking for her replacement and when u find a girl that is 100% into u, dead it. but when u dead it with her, be resolute. do not waiver. dead it. and when/if she comes back to u, dont fool urself into thinking giving her another chance will change things. u can fucck her, but know right now she aint the one.