Allo in a relationship with a grey-a here, over 7 years now. I remember your naivety well, and know there's little I can say that will change your mind. I'm not saying that to be mean, I was in your shoes once and faced the same dillema. So all I can say is: you are in for a world of hurt, the sooner you get used to that idea the better. That isn't a negative, it's just the voice of experience talking.

Firstly give up on the idea of decreasing you libido, that way lies madness/serious bodily harm. Learn to deal and how to divert your attention. Pick up a hobby or five and focus on them when the mood takes you. I'd recommend working out and video games. Good mix of physical exertion and time consuming concentration.

Second, understand the feelings are going to get more intense with time, not better. Regardless of how accommodating her boundaries are (sex repulsed or not) you will start to miss or wonder about the emotional side of sexuality in relationships, ie what if feels/felt like to be desired. This stage will be the true test of your resolve, and is so much more painful than just a lack of physical intimacy. Consider yourself forewarned.

Thirdly, self flagellation over your libido will only serve to undermine the other parts of your life. Acept that at times: you will be horny when you don't want to be, you will feel lonely in her company, you will get envious of other relationships, you will wonder if it's worth the hurt, will feel unattractive even if you know you are. Dwelling on these feelings will only drag you down mentally with friends, at work, during your hobbies etc. learn to float on top of the thought chaos if you want to keep your sanity.

Finally, and probably most importantly, learn to be less sensitive. Telling people on the internet to fuck off because they have opinions you don't want to hear tells me your skin isn't tough enough for the path you've laid out for yourself, you will need to work on that.