I think I'm going crazy!

Me and my partner of 12 years, were finally able to starting to have a baby last October (serious medical complications made it dangerous for us to try).  Now that we have got a few things figured out, we've started trying.  Because we want babies so badly, I was dumb enough to think that we would get pregnant nice and quick! Well, it's now June and there hadn't been the slightest flicker of a pregnancy...and that's where the story changes a little.  Recently I've started to manifest signs of pregnancy.  I'm finding the slightest sign, the tiniest symptom and BLOWING it out of proportion.  Before I get my AF I'm convincing myself I'm neautious, I get dizzy... one time I even thought I felt the quickening...  Then I get my cycle I go into a depression cycle in which I beat myself up and feel sorry for myself, meanwhile my husband beats HIMSELF up, thinking it's his fault!  I'm currently into day three of my most recent flow, yet again thinking I was pregnant... I've decided to try to change a few things about myself.  I'm going to incorporate a weekly workout schedule (try to loose some of the depression doughnut) as well as some other self help stuff to try and take my mind off my craziness and hopefully make my body a better home for the baby that I one day will hopefully carry... Any helpful ideas???