I have sometimes wondered if it would ever happen, but I have never considered giving up. The first year was the hardest truthfully, because I still had high hopes that my odds were good.
As crazy as that sounds, after I passed the year mark and the IF diagnosis, and came to terms with the reality of my situation, it got easier. January will be 24 months, and 19 cycles for us. We have Unexplained IF, and our RE gave us about 4% odds of conceiving naturally.. We are still trying. I give myself a day to feel disappointed/cry/react however I feel each CD1, and then I try to move on, because for me, dwelling on the negaitve can quickly bring me down.
I think it's good to allow yourself to feel how you are feeling, but also acknowledge that if there are things/situations/etc. that make things worse for you, to take a step back. If I am having a bad day, I don't get on FB because I don't want to resent other people's positive news because I am having a bad day.
Anyways, I went off on a tanget, but hope it helps. Just my 2 cents. Keep your chin up.