Hi Squidgymo,
I'd like to join

InfjEpic in welcoming you to the community. I'm sorry that you have been dealing with suicidal threats from your ex. That is so hard to deal with. It's obvious that you care about her and want to help. But you can only be helpful if you have taken care of yourself first.
InfjEpic has shared a link that has a lot of useful information in it.
Does your ex have supportive people around her? Someone you could contact that would be able to intervene during times of crisis?
Keep posting. We're here to support you.
heartandwhole