Mismatched Sex Drives and Mixed Signals

First, everything I'm saying here is how I honestly feel. I know that I should trust my girlfriend, and I absolutely do, but I'm having doubts about myself. My girlfriend and I have been dating for about 3 months after being very close friends for almost 3 years. Every aspect of our relationship is wonderful, but the sexual aspect has lately become confusing, and I'm not really sure how to handle it. We have always communicated very well, and when we started dating, we talked about sex. She was thrilled with my enthusiasm for cunnilingus, as her previous relationships had been lacking in that department. She had expressed how much she loved receiving it. When we had our first night together, I made sure to focus on that element. She seemed very satisfied, and even said so afterwards. However, I could not tell if she had actually came or not. I talked to her about it, and she said hesitantly that she had, but ultimately she doesn't care about orgasm as much and that was not important to her. This was the first confusing thing, as prior to this, it had seemed like due to her enthusiasm for receiving oral that something like not caring about orgasm would not be the case. I feared that perhaps I had not satisfied her and she was trying to spare my feelings, as I have previously had issues with self-doubt, especially in the bedroom. I brought it up again later and while she reassured me she was happy, I still had the feeling that maybe I wasn't doing very well and she was again trying to spare my feelings. From there she seemed hesitant to want to talk about it, and I have been afraid to bring it up since for fear of being bothersome, even though I have not really had a resolution of my doubt. Another element that contributes to this general unease is that she generally does not initiate sex, I am the one who does. When I do, she does not decline, and generally seems to be enjoying it, but the fact that she does not ever initiate it is somewhat troubling. That is coupled with the fact that she told me in her previous relationships, her SO's stopped having sex with her after 6 months or so, which presumably leads me to believe that she had been one to at least express interest in having sex. The most troubling part of all of this is that she has told me multiple times that she just doesn't really care about sex that much, but things she has said with regard to sex previously have been contradictory to that statement, which leaves me feeling confused and self-doubtful. I'm looking for some outside perspective by anyone who may be able to shed light on my situation, or provide advice for how I should go about dealing with what I'm feeling. Thanks for reading.

Do cunnilingus until your tongue muscles hurt and all you feel is pain. Take small breaks of rubbing your nose on her organ if the pain is too strong - this is how I make sure girls orgasm during cunnilingus. Also, you should really inform yourself about it .. cunnilingus is quite a bit more complicated than it may seem if you want it to be pleasurable enough to cause orgasm. It will help if you couple it with other actions like caressing her waist or, if she's on top of you riding you face, massage her back.
I also suggest trying different condoms. I have found that the most pleasurable type of condom is Durex Intense Sensation(?) - the one with bumps.

I hope cunnilingus isn't all you do because this might be a factor in her not initiating sex. Vaginal orgasms have always been better than clitoris ones in my experience.

Ask her what she likes most and what she would like you to do. Sex with new partners is a learning experience because people have different preferences.

Some women cannot physically orgasm ever. Many others only rarely when the stars are right regardless of how they feel or what's done.
Don't make her feel self conscious or that somehow she's failing you for not orgasming.

It seems to be true that many women who have secure relationships stop seeing sex the same as when things are 'new' with a person. I think you can only do you best. I used to manipulate my wife until she came like crazy, but after we'd been married she told me that didn't do it for her anymore. And that's a shame because I can't have sex now and manually is the only way I can do it. Guys are pretty much straight wired for sex but girls are more complicated. I think you should do as suggested above and give her the best you can. If she want's something different she needs to let you know.