Is there any chance you can get some individual counseling to help you find the steps to work through these issues? I also faced up to the fact that I need some help taking the edge off my anger and sadness, and I made an appointment to see if I need an anti-depressant. Maybe that could help you too.
In the meantime, make a decision to stop focusing on him, and start focusing on some smaller, more achievable goals. Something that really helped me was focusing on my home environment, cleaning out the invisible corners, straightening things up, even spending the $5 at the grocery store for some flowers for MYSELF to make ME smile a little every time I'm in that room. I also used this website (warning: salty language!) to help motivate me to get off the couch, wipe my tears, refocus my energy, and do something with my hands.
Un-**** Your Habitat
I also found that I could hand my kids some lysol wipes or a duster and they were perfectly happy flitting around the house with me, chatting and cleaning and listening to music. A teenager and a toddler, no less!
Some days I struggle more and some days I struggle less. I've decided to try to focus on my kids in a positive way and spend some of that nervous energy making our home environment more homey.
A lot of people on this board also recommend finding a way to exercise. Like, a lot. Exercise is the best natural way to help with depression, so ANYTHING you can do to get up and do something is a victory. Baby steps, baby steps. :ghug3