It hurts seeing my ex addicted to me do cocaine just to get through the day

My first relationship was with the most beautiful girl I had ever seen. It was a whirlwind relationship and it was love at first sight. We were friends for 3 months and rarely spoke to one another. She would come visit me and help my then wife now ex-wife recover from her strokes. After those 3 months, I had a crush on her but I didn't think she felt the same. She was 5 years younger and 6 months ago I thought she was too young for me. One day she posted about wanting to die as she was raped by her sisters boyfriend. I was on her fast and she told her whole story to me. I told her how I felt and she told me how she felt. In just a few weeks I was on my ex-wife's doorstep with divorce papers. It was the happiest time in my life. Then 2 months later my now ex came to visit me and told me she was pregnant. She and I have a 9 month old daughter. 3 months ago I broke up with her. I'm rarely home and she was depressed. She started using cocaine to feel better now she is addicted to it and started to have seizures from using it. She has seizures caused by epilepsy. I was addicted to cocaine and stopped using it. She was still clean when my daughter was born but now she is addicted. She starts to get clean then some memory will pop into her head and she starts to use it again. I've been bruised and used by her. I've never been this depressed. I don't know what to do to help her. I really want to help her and I'm at a loss. I've been addicted to cocaine and stopped after 3 months. She has been addicted for 3 years and only once was able to get clean. I have a headache from listening to her cry. This is what happens in life.