Having suicidal ideation can occur due to many mental health issues, commonest of them being depression.
If she talks about it, do not ignore her words.
Next Steps
Please seek immediate help for a psychiatrist and a psychologist
Health Tips
Dont push her when she is having an emotional outburst, handle her calmly, try to be empathetic , politely ask her to vent her emotions and show her that you are listening.