I've low-key followed a lot of red-pill stuff for a while and just recently decided to get active here on reddit.

I'm a Christian, workout 5x/week, always been muscular and toned since we started dating, I bring in plenty of money (we're not high-rollers or anything, but she's able to comfortably pursue hobbies, etc..), and I have been steadily advancing in my career faster than those around me. I'm firm in my leadership. I allow her preferences on things I don't care about, but she knows that on things that I do care about, and on things that matter, I'm the final decision maker. And she's happy with that. She doesn't challenge my leadership

We are generally happy with no major relational problems--EXCEPT our sex life.

She is convinced that she "just has low libido." She shows affection to me in other ways on a very regular basis, including physical affection (leaning into me, wanting to hold my hand even when we're sitting down, hugging and kissing me, wanting to cuddle, etc...). I flirt with her on a regular basis, including physical flirting (randomly grabbing / slapping her butt, kissing her neck and rubbing hit boobs from behind, etc...) and she will respond positively to it. But, when it comes to actually getting into bed, she has to really work hard to exhibit any desire.

She's willing to have sex on a somewhat regular basis (few times a month, maybe once a week), but it's definitely out of a sense of obligation or "service" to me. She's not quite starfish (she knows I hate that and won't engage with it), but it's still minimal interaction.

Part of the problem is that penetration can be painful for her no matter how gentle I am (I think this might partially be due to her not being in the mood), but she won't let me use my fingers or mouth as an alternative (she thinks oral is disgusting). So it's just not pleasurable for her. And in that case, I don't blame her. But if she'd let me go down on her or use my fingers, she'd probably enjoy it more and might even get more naturally lubed up for penetration.

So here's the question: Is this on me? I can't be the only Christian guy in this situation. But all I see on here is either divorce (not an option) or "Man up, get in shape, etc.." (which honestly doesn't seem to be the problem). I'm all for self-improvement and taking responsibility for yourself first, but when I honestly look at myself, I think I'm doing a pretty damn good job as a husband. I can't think of any reason she shouldn't be attracted to me, and as far as I can tell, outside of the bedroom, she's totally attracted to me. So, is there a possibility that she has a problem? Is it possible that many Christian women have psychological issues about sex being dirty, shameful, or taboo, and that this causes unhealthy sex lives in marriage? Is it possible that not every marital problem boils down to the man not being "alpha" enough?

Edit:
I wasn't being lazy. I figured I summed this up above.
Stats: I haven't measured BF in a while so not sure, 5'11, 195lbs, bench 225, squat 495, Curl 65..
Reading: I've read most of it, but haven't kept a detailed log.
Finances: Accounting, Income is good and has been on a steep up-hill trajectory last few years, Very good future prospects, we have some school debt but nothing overwhelming.
Spiritual: Very mature, close with my elders, study theology with them, regular quiet time and evangelism.