Starym:
It seems entirely possible to me that something may have occurred that has driven her away from romanticism. It's possible that maybe something happened while you were being intimate that really offended her, or possible that she's become afraid of being intimate due to something you've said during the day. It's also entirely possible that she's looked on your past intimate cycles, thought herself to be too brazen, and has toned down accordingly.
I would suggest talking to her about it. This is a tough topic to approach. Make sure you approach her openly, calmly. Try not to use attacking words, or any manner that may look like an attack. She's likely really uncomfortable about the topic, and may shy away easily. Try approaching it like, "We don't make love nearly as much as we used to. Can we talk about that?" or, "I can't help but notice how often you pull back when I want to make love. At first I thought you were just tired or stressed out. Now I'm worried there is more to it. Please tell me what's going on."
Now, she may reply to this with some sort of accusation, it's important that you do your best not to take offence. Try to remain open to the conversation, and calm. Try not to pressure her, as the pressure you may be putting on her to perform may be the very thing that's turning her off.
If she accuses you of being the problem, try to be supportive, "You're right. Maybe I haven't been the nicest person. Maybe I'm frustrated, too. Can we figure out a way to put things back together?"
It's important that you're both working together on the solution, and that you're not placing blame on anyone. Remember that you're a team in this.
Another thing you may want to try is just going out on a brisk walk for like 20-30 minutes... Some research has shown that women tend to be easier to arouse after intense aerobic exercise..<p>Just my 2 cents.
DarcNiobe<p>Many of the quotes in this response were taken from a book by Dr. Paul Coleman "How to Say it: For Couples"