I was totally in your shoes. I had a heart attack last Oct due to not watching sugars, weight, etc. Was 59 at the time, had one stent put in. Since then I have lost 45 lbs, have totally changed my lifestyle, and my labs are great!! In the ER that night I decided I didn't want to die... If you get depressed following all this, it's normal. I also beat myself up for a while. Went to cardiac rehab for a couple months, which really helps with reconditioning, strengthening the heart muscles, and is great for support from others going through the same thing.
Hope you're feeling better and keep me posted!