DS was in a relationship for about 2 years. I never really took to this man. He seemed really distant and cold to me and not engaged at all in the relationship. He is a bit older than her (She is 35, he is 46).
He is divorced with 2 DCs, now early teens, from a previous relationship. From what I understand this was a very acrimonious split and the EXW apparently didn't let him see the children and took them away to America without his permission. (Although for some reason I am a little cynical about his version of events). He now has contact with the DCs and the EXW, pays maintenance etc. He is financially and professionally secure, owning his own home and being a partner in a practice.
He has always said he didn't want anymore children. Fair enough.
About 18 months ago, DSis became pregnant and had a termination. She was very upset by this. 6 months ago she becomes pregnant again and decides to keep the baby.
Things are very strained between DSis and her partner. He clearly isn't engaged and she tells me at Christmas she is pregnant and that he hasn't touched her affectionately or sexually since.
Things rumble on but she is not able to get excited about the pregnancy as he is treating it like the biggest disaster on the planet. (But never has the courage to end it or say he doesn't want the baby). He "doesn't know if he can cope" with going to the first scan, then does but cries all the way through it (Not happy tears). I am infuriated he "blames" my DSis for this - the man is a fucking vet so he knows how reproduction works and could easily have worn a condom or had a vasectomy if he was so bloody certain he didn't want more children.
They finally split a couple of months ago. He thew her out. She is devastated although personally I think better now than after the baby is born and that she is better off without him, but easy for me to say.
She has found somewhere to live and he is going to support her financially but she is so hurt. She spent a month sharing a room with my brother at my parents a 6 months pregnant 
She has confided in me she is self-harming (digging great chunks out of her arm), having suicidal thoughts and sometimes wants to "cut the baby out of herself"
She is seeing a "vulnerable mothers" midwife now who seems very good and also a Psychiatric person (not sure if a CPN or a Psychiatrist). Hopefully this will help.
My DM lives close by and she and I will support her and the baby as much as we can emotionally and practically. DM will move in with her for a bit once the baby is born and I am on hand to help whenever she needs me.
But she is so hurt and I am so worried about her. I can see her having a huge breakdown. She is terrified she won't love the baby.
I just don't know what to say to her or how to help her :(