How do I go about getting custody of my child after it is born?

[williej]

     Hi there. My name is Willie and I have been with my girlfriend for about 7 months now. She moved into my home three or four months ago and started self-mutilating herself. She tried commiting suicide many times (slit her wrist, tried to jump out of the car when mobile, etc.) and all of this was associated with her horrible constant mood swings. After discovering she slit her wrist the first time, I immediately took her to see a therapist at a mental health facility the next day for an evaluation. The therapist recommended inpatient treatment and for me to have her involuntarily committed. Which, I did. Now, she has been in the state hospital for almost two weeks now and been diagnosed with the following:
Border-Line Personality Disorder
Bipolar I, most recent episode severe manic
Post-traumatic stress disorder (sexual abuse of child)
Methamphetamine abuse
Alcohol Abuse
etc.

     Since her admission into the state hospital, I have learned that they found out she is pregnant with my first child! We had no idea and all the tests were negative she took before she left and also negative at admission into the state hospital. They put her on Lithium, Seroquil, and Visteril at first; then, they immediately stopped all the medications because of her pregnancy (after being on them one week in the state hospital).

     Anyway, since then I have decided there is no way I think our relationship can continue if she can't get any better. Therefore, I am seeking help on how to get full custody of the child when it is born. I am scared that if she has the child that the child will experience both verbal and physical abuse from her all the time. I am only 23 years old and she is only 20. I have a full-time job (she is unemployed) and I also take online classes toward my Bachelors in Psychology-since I am almost finished with my degree (she has a GED). I know in most cases the mother almost always wins full custody rights; however, I know I'd be a much better parent for the child- giving it a much better home and environment to grow up in. I also do not suffer from any mental illnesses, as she definitely does. Any suggestions anyone on how to go about this (besides just going out there and hireing a lawyer, which I will do when the time is appropriate)? Do I have a fighting chance winning full custody in the courts? What steps do I need to take?

Thanks,

Willie