What can I do ?

I hope you are well, I am writing this to get it off my chest and because I want to hear a third person's opinion.

I am 25 years old and I have been in a relationship for two years that became a toxic relationship and source of unhappiness in my life in the last 16 days I received 731 insults from my partner, whenever I tell her to go out with a friend she insults me, she is distrustful , She is very jealous and our relationship is long distance, we see each other every month and a half for 20 days, lately when I had decided to end it she has hurt herself, a few days ago she cut herself, and I am afraid that she will hurt herself more because she has told me that if something happens to her it will be my fault and I will not go to her funeral, I know that I have made mistakes, I have reacted in a very bad way. I know I have made mistakes, I have reacted aggressively and I have hit her back ( this happened 7 months ago when she pushed me to a motorcycle and then I hanged her from the rage my lights went out ) I have sought psychological help to control my impulses of anger and thank God I have improved a lot and live calmer, she also gave me to understand that the relationship I was in by not changing neither the limits nor the respect only increases the cycle of pain, I love her I am 20 days away. Days away from seeing her, I don't know if I should go and abandon everything, talking to her about ending it is impossible because she insinuates that she will hurt herself, the truth is I don't know what to do, I don't know how to get out of the cycle of pain in the relationship and I don't know how to end it definitively with my partner, thank you for reading this.