It seems like sex was a really big issue for a lot of us. My H thought he was a great lover (not implying anything here, COG!), but there were a lot of things he did that I didn't like...and I never said anything. When this was going on, I was mad. How could he not know? Now I see that the poor guy needed more obvious clues, like OUCH! STOP!! lolol
Anyway, as our R deteriorated, I didn't consciously withhold sex, but my desire waned to nothing. It was partly bad sex, parly hormonal, partly due to medications, but largely due to unresolved anger about other issues (as I see now). Because I was angry with my H, I never made any real effort to resolve my problems with desire. Oh, I said I was trying, and I did make some token efforts, but I did not COMMIT to changing. As you said above, that is the key: she must really WANT to change, and for some reason, she doesn't.
COG, I think you're going to have to lay it on the line with her. She needs to know that this is a deal-breaker for you (if it is). Once you decide in your heart what you really want and need, I think you will know what to do. You will have to be resolved in your own mind b/c you will have to be strong to follow through on whatever you decide.
God bless, Nicola
Life isn't about finding yourself; it's about creating yourself My thread: Trusting God's Plan