Hi nishty, ive grown up with alot of sisters and unfortunately there has been some history of domestic abuse, with any form of mental ill health there is a uniqness to how to deal with a person and its difficult to advise based on that fact alone.
You are clearly thinking of her and how to help which is great to see! The thing is, when it comes to traumatic events there are no quick fixes, it takes time, support, understanding and empathy as well as much more.
If your partner is recieving any treatment for mental health you could try working with her therapist or gp shpuld she be okay with it. Dont go behind her back and speak to them it will cause trust issues as its extremely personal for her... If she blocks or changes the subject when u bring things up dont push, or get frustrated, simply reassure her that should she feel ready for your help to simply ask, or hint....
You cannot help people until they are ready and accepting of help so the best thing i think you could do is continue to support and understand her as best you can. Understand that the things that have effected her for the worst grew over time and with the right care, treatment, support and drugs she will, in her own time be ready to take the next steps of the healing process herself, she may need you to hold her hand at times, or give her time alone to process things.....