Sounds like a good boundary.
Have you tried al-anon or educating yourself about the disease? It can help you deal with/ understand some of the issues you have been dealing with. I found these things very helpful!
I gave My older daughter's father "one last chance" before I left him. It worked for me because we both knew what was at stake. I didn't cave when it happened. I just said I could no longer live my life on "one more chances"
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