SO losing hope

Hi ladies,
In need of some advice...My husband and I have been TTC baby #2 for well over a year now. I got pregnant with my first in one month and it was a smooth and healthy 9 month pregnancy with no complications. 
Cut to...I've had four miscarriages since then and no sign of getting pregnant. I've used ovulation tests and temping and just can't seem to get it. To make matters more stressful my husband seems to be losing hope that we will have a second child. 
He just doesn't seem excited about the idea and even said he can't emotionally invest in it anymore unless we make it to 12 weeks. I feel frustrated like I'm in this on my own. Any thoughts or words of wisdom that could help?