I hear you are in a lot of pain. But I also hear he is a cocaine addict. I’m neither an expert nor familiar with your situations but it sounds like whatever’s going on in your relationship with him, the coke comes first and last even if neither of you wants it to. I think a lot of your questions that start with “Why...?” or “What...?” or “How...?” pretty much are answered by, “cocaine.”

“Yes but why didn’t...”

“Cocaine”

Etc.