I can understand your feelings and it's not a fun situation to be in. Like you, I went back and forth - sometimes I would be able to keep things to myself and then other times I would share things with my mother. Every single time I did, it turned out badly. But, I continued to try because I wanted the relationship with her so badly.
When I stopped drinking, I knew I had to put up a strong boundary around her and I did. We didn't live geographically close, but she would often phone and I would talk about the weather, etc, but never about anything happening in my life. It was hard for me to accept that it had to be that way, but once I did, I began feeling much better.
I think you need to work out how much contact you want with your mother. Try to remember to put your needs first. I do believe (at least for me) this is codependency, so it's possible that therapy could help.