I can understand exactly where you are coming from. I had the same only my husband already has two boys from a previous marriage (they are 13 and 16 yrs now). He wanted to let it happen but I was 45 when I married him and time was of the essence. I did all the research, bought a fertility monitor and test sticks for every occasion, temped for God knows how long (best part of 2 years+) and tracked everything on Fertility Friend.
I got so stressed with him not taking any interest in what I was doing (or at least that's how it seemed to me). One of my friends advised me to try not to obsess that my marriage could suffer as a result, so I literally gave up. I said I called it a day because of my age and that was the primary factor, but the secondary factors were huge. I just started to really dislike his attitude and lack of support. When I told him that I thought we shouldn't try any more as nothing was happening, he just accepted it. He didn't even give me a hug the way I thought he might. He has never discussed it with me, although I have tried to talk to him openly about it and now I have just accepted that he didn't understand and will never understand how I have been affected.
He really is totally different to me. Part of me will always believe that because he has his boys, it is not the end of the World for him, even though he says this is not the case. I am 49 now and we won't have children together now. I feel most of the time that I have coped with it and learned to accept that nature takes it's course and I must accept the things I can't change. But a tiny part of me will always blame him for now trying harder. There were more months of missed opportunity thanks to him than months of strong possibility.
Men are strange creatures indeed.
Take some solice in the fact you are young (no doubt much younger than me) and that it might take you a lot longer than if you charted, temped and monitored each month, but if you have a good few years left to try, then try not to fret, try to learn to accept defeat some months and somewhere along the line you will get your wish to become a mother.
Wishing you good health, happiness, peace of mind (and lots of man-tolerance-patience) and a big fat bump in the not too distant future.