My husband and I built our own home as well. It was the hardest thing I have ever done. We picked rocks and poured our own concrete foundations with a shitty harbor freight cement mixer. At times I thought I was going to lose my mind, but we did it. Podcasts saved me. I would set up my work area for the day, pick a pocast and let my mind wander while I put up yet another peice of drywall.
Hang in there. In my darkest moments I had to remind myself that every action was a step forward. Even just running to the hardware store. It is all a step forward. One step at a time, one day at a time. We did it, and you can do it too. I'm rooting for you buddy! It does get better!