To the OP, I was (and in a way still am) in the same position. I too was a secular person ever since I was young. I love(d) science and reason, and hate(d) irrationality. I bought into the idea that reason and emotion are opposed, that I was a being split in two: a Man, and an Animal. The Man was the reasoner, the scientist, etc. The Animal was my emotions, sex, even physical activity like sports or exercise (or even being outside and enjoying it in any way). And so, ever since I was in elementary school, all the way up until my senior year of high school (I loosened up a bit my sophomore and junior years but really didn’t shake it in any meaningful way until senior year), I suppressed laughter or smiles, I stamped down any sexual urges, intentionally avoided interacting with anyone outside of school, intellectualized almost all of my activities so they had little emotional impact, etc. I also became very overweight, but suppressed even my shame of that as it too would be a concession to the idea that my body mattered, which to me was a sin against reason.
Well, in terms of my conscious statements, I believe none of that crap now. And I’ve made some progress in various areas. For example now I laugh and joke and smile. I don’t intentionally stamp down my emotions. I don’t suppress sexual feelings and shun them as if they’re dirty. I’ve even started eating a lot better and have lost 20 pounds in less than thirty days. However, the after effects still linger. Even though I don’t try to be, I still project the image that I am a brain in a jar. I don’t have strong emotions, they tend to be more superficial. I find it hard to be motivated to do things (as my ability to value things, and feel that, is limited at this point from years of repression. My emotions about sex are messed up too, as a direct result.
However, I have made improvements, and continue to do so. How? By understanding that sex isn’t (or doesn’t have to be) “lower”, it can be great. That I am not a Man and an Animal, I am a Man (and men are also animals). I have emotions, and reason, and they can and should work together to make my life better, rather than at cross purposes. I am a union of mind and body, and the needs of both must be met (though I still haven’t been able to bring myself to exercise, that one is difficult for me). It is both good and bad to here that someone has had a similar experience as me- a secular type person who has problems with sex because it’s too “animalistic” or “impure”. Good, because I’m not alone in that, bad, because that means there are others that are also in a bad way.
Here’s hoping we both get our s*** straight.