Here comes the guilt again

I saw a discussion thread about guilt tonight and feel it might be helpful to write about my feelings in a "non public" forum.  I met Kirk when I was 15 and married him at 20.  He was in the navy, so after we married, we moved to Virginia.  2 years and 1 son later, we returned home where Kirk continued to go go college.  A former high school drop-out - he got his GED, graduated from law school and passed the bar!  Everything was going great - or not.  I knew Kirk dealt with bouts of depression from the time we met, but the severity of his disease wasn't known until he reached his late twenties. 
We were married for 32 years, and throughout that time, we dealt with worsening depression, tons of medications, shock treatments and multiple hospitalizations as well as alcoholism.  I loved Kirk with all my heart and stood by him through all of this - taking it upon myself to be the only financial support for our family as well as doing everything I could to avoid another break down. 
So where does the guilt come in?  Well, just a few months before Kirk passed away - alcohol was becoming a BIG problem.  I gave him an ultimatum that he needed to go for treatment.  He signed himself into a rehab facility but by the 2nd day, refused to participate in any of the activities and was asked to leave.  When I went to pick him up, I told him I was at the end of my rope.  I could not take this any more. If he continued to drink, I was done.
Well the next few weeks were bad - he went back to drinking, and I told him I couldn't take it anymore.  We would need to separate.  It was taking a toll on me as well as our 15 year old daughter.  I began planning on where she and I could go to get away for awhile.  He begged me to not leave him, but I truly felt that there was no other answer.  He knew I loved him dearly, but I couldn't continue the way things were.
In fact, on the Sunday before Kirk died, my oldest son and I were talking about my daughter and I coming to stay with his family until we could figure out what to do.  Thursday morning, I found Kirk dead on the floor by our bed. 
The coroner said is was "sudden death due to cardiac arrhythmia" - but I know he died of a broken heart.