Becoming depressed

About 12 weeks along now and I've lost a lot of weight and energy. I've missed a bunch of work and my sick days left are numbered now. But the worst worst worst part is not being able to take care of my son like I used to. He's 1 1/2 and sometimes I wonder if he even likes me anymore. I'm no longer fun and he just wants daddy. I'm too sick to be alive. Only visits to the ER for fluids are keeping both baby and I okay. Please God let this end soon. Any success stories? I've never had this before. How do you get undepressed?