Health insurance questions.

I was just wondering if anyone has any experience with health insurance. I'm 25 and I have my own private insurance, not through an employer. My SO is still on his dad's insurance. Our daughter is on Medicaid (micro preemie) all of her care is payed. My insurance is becoming too expensive. I'm not working right now and haven't for about a year (bed rest, 123 days in the NICU and 2-4 dr appointments a week, just not enough time). My SO can get his own insurance (works for the same company as his dad) can I get in my So's insurance, if he buys his own? Can I qualify for Medicaid?? We are not married but have been together for 6 years, living together for just about as long. Any help would be great.