There's a lot of us who have been in a similar situation. DH and I have been trying for almost 3 and a half years and have had three miscarriages.
I recommend seeing someone about it. I don't know where you live but I found ShoreWomen to be very helpful if you live in Auckland. I also recommend acupuncture, I don't know if it was coincidence or not but I got pregnant shortly after starting acupuncture. I also recommend charting (on sites such as FertilityFriend) if you aren't already to make sure you're doing the bad thing at the right time.
Even though no one has posted for a while, if you post in here, everyone's been through it and are super supportive -
here
Also, not too sure how old you are but these girls
here are the most amazing people and I'm lucky to have had their support on my long journey.
Best of luck xx