Wow, the situation gets more tangled! Sounds as if at 27 she needs some serious "Tough Love"

I'd tell her that she's completely on her own to deal with this -- in all ways, financially, emotionally, and physically. Tell her you won't be there to listen to her boo-hooing how she got herself into this mess. If she starts to complain, get up walk away, hang up the phone... whatever you need to do to get your point across that you are not interested in her whines about her present situation. You'll be there to talk when she starts planning how to fix her life, but not when she's complaining of where she is.

Tell her you will not be there to babysit while she goes on doctor's appoitnments, or after the baby is here. You won't so much as buy one diaper or bib. By doing all that she will no longer have people sitting by and helping her continue her self destructive ways. ITs going to be HARD and you will DEFIANTELY be the bad guy until she starts seeing clearly. Thats what my grandmom had to do with my uncle who was so messed up on drugs. One day he found himself in jail and REALLY had no choice but to accept his actions.... and now my uncle is Mr. Pillar of the community and an A+ father and stepfather.