As hard as it's been for me to find out I'm not pregnant when I thought I was, I think I'm going to way in for getting your hopes up.
I guess what I'm trying to say is that as hard as the downs have been for me, I've loved the ups. Early on ttc, we thought I was pregnant. I'd watch all the pbs specials online about the begining of pregnancy, and according to what I thought I knew, the baby had implanted as was building a placenta. There was this incredible heat coming off my tummy but not higher up, and we thought it was all the new circulation happening. My DH sat with his head on my belly, and it was this little wonderful moment of awe. We were wrong, but I wouldn't give that moment back.
Some people (my DH among them) do better just keeping an even keel until they know for sure.
I am finding I do better if I go with what I feel when I feel it-letting myself do a little fantasizing, and just crying when I feel like crying. If I try and fight either one then it just takes longer. If I fight the enjoyment, the crashes are harder and last longer.
I've also had to surrender a lot of my sense of knowing the reason for all this. Accepting that it's a mystery allows me to let go of trying to make sense of it, which makes is less all consuming (well,slightly less)