Reading your post nearly made me cry. I'm only 23 too, but when I was in college I was in a relationship with the man I thought I would marry and I was in the exact same situation. He had the same thing happen at nearly the same age and told me about a year into the relationship. At the time, his libido was higher than mine (which was not high at all), but I had health problems I didn't know about thoughout the relationship and, luckily, have had them taken care of. He swore me to secrecy and I kept that vow until relatively recently. (Even now, I have only discussed it with my therapist and a close friend who does not know him, but it was a relief to have someone else know what I went through, even years later. It still hurts to think about and to know that there's a part of my life that affected me deeply that few people will ever know about.) Please, please do not keep this to yourself. I did and it completely ate me up inside, making me randomly angry and sad. I would say I didn't want kids because I didn't want him to think I wanted what he couldn't give me and he would never talk about the situation with me, he barely acknowledged it. In the end, the lack of communication really hurt our relationship and me. It's really hard when friends talk about your 'future children,' even jokingly, and you are the only two who know the truth. I used to get weirdly slightly angry when I heard about other people's pregnancies. Once, I got a text about a good friend having a baby with his girlfriend. I was at dinner with friends at their apartment and I left the table, locked myself in my car and cried. Inferitlity is not something you want friends to know or anything, especially if he's secretive about it, but you should talk to him about opening up to someone you can trust, like a close friend. Alternately, a therapist is required to keep information confidential, so that's a good option if you are open to it. (He may have issues with self-worth and masculinity that he could benefit from talking through too. I can't speak for your man, but mine seemed to have issues that would have benefited from us talking with an unbiased professional.) Talk about the infertility with your partner and be open, but be sure he knows that you love him deeply and that you think he is a wonderful man who is everything you want and need. I had the same issue with birth control, but I believe if you're not ready for a child, then the timing is not right, regardless of the circumstances. However, the chances of you getting pregnant while off birth control in this situation, as far as I know, are still pretty much impossible. Once you love someone, it probably won't change the way you feel about them, but you do need to acknoweldge your pain and give yourself allowance to grieve the future you imagined for yourself. You are blessed to be in love and to have someone to love. Nothing is better than that.
After this guy and I broke up (for reasons of his own that I still don't entirely know, but not pertaining to the fertility issue that I know of- AND I was going through a rough time medically towards the end that I kept to myself, but took out on him- I was a real horror.), I dealt with my own fertility issues and began volunteering with foster children. My health issues have been resolved, but the experience stayed with me. It was so wonderful. It opens your heart to how amazing fostering and adoption can be. I am a very spiritual person (or have become one anyway) so you may or may not share my thoughts on this, but I sometimes feel challenges like this are there to open your heart to another way of life than you may have imagined that is the life that will bring you the most joy, despite the struggles. If you choose to adopt in the future, that child will still be yours and his, taking on various attributes of your personalities as he or she grows and thriving off the love you have. Adoption is a really great option and there is such a need for it. I remember one little boy who was terrified of everyone and had been mistreated finally taking my hand and smiling up at me. It was so awesome.
My heart goes out to you. You're not jumping the gun. It is a very painful situation and it sucks. Please, please feel free to contact me on this forumn. I can't tell you the details of my situation because I respect the privacy of the man I loved, but I felt a real need to post this because I have been in exactly the same place and I want you to know you're not alone. Gosh, I've written a **** book, but I have a tendency to talk too much...I hope you are ok. You are so lucky to be in love, to have love and to have such an open and loving relationship. Encourage him to be open with you. It still hurts me to think that my ex kept something from me for quite a while because it didn't change an ounce of how I felt for him or how much I wanted to be with him. Be supportive of him and encourage him, but give yourself time. It takes time to get used to new information, but, if you let it, this challege can really strenghten your relationship and your love.
With love and best wishes,