Feeling frustrated

I'm really overwhelmed and do not know what to do. So my husband got out of the army in February, he suffers from PTSD, and a year ago at this time he was extremely suicidal. He's went through months of therapy and even stayed in the hospital last November. Anyways, since he got out I figured I would give him time to de-stress and get used to being a civilian again, so I was working 90 hours a week until this past May. (Then I found out my body became immune to my birth control, and I was 2 months pregnant). Well, anyways, so I'm 28 weeks pregnant tomorrow and I've been working 40 hours a week at a very physically exhausting job, and my husband still will not find a job. He literally will not even attempt to look for one or even apply anywhere. I'm trying to be patient and thoughtful because of all of the stress from last year and I don't want him to feel overwhelmed, but he doesn't cook or clean, or do anything unless I beg him to do something, and as my pregnancy continues I'm feeling seriously overworked and physically in so much pain. He's obsessed with siting and playing video games all day and night. The other night my back was aching so bad and I was so short of breath I thought I was dying, and as he saw me laying on the carpet trying to catch my breath, he stayed playing madden giggling and talking to his friend online.  I feel like I'm married to a child sometimes. I feel so alone, and so confused. This is NOT the person I married or even the person I fell in love with. I don't know what to do because he promises he will do this and that and then he doesn't pull through at all. I feel like if I push him too far he will be pushed back into suicdal thoughts again.  I just am at such a loss for what to do.