Toxic relationship?

I’ve been with my fiancé for 2 years we recently split due to constant lying and arguing on her part, she didn’t take the break up well at all, she ended up coming to my job yelling fighting with me kicking things over and ended up taking a knife close by grabbing me and putting it to her throat beginning to bleed and told me “ I can’t live this life without you” ended up telling her to leave and that I would go outside and talk to her she ended up going outside and that’s when the cops were called on her, I just don’t know what to do, I love her so much, but I’m just at a complete loss.