I read your story and thought--this is me! I was a little older, but had very similar experience. Like you, I had near total blockage in LAD. Went on meds. But meds made me sick, so I started doing a lot of reading. I highly recommend Gary Taubes Good Calories, Bad Calories (GCBC). This started me thinking differently about diet and heart disease.
Given that you had another blockage develop, you can see that the meds don't always treat the cause. No one knows precisely the cause of atherosclerosis, but if were you, I'd look into a low carb diet. Taubes in GCBC describes the work of RM Krauss (google "Krauss carbohydrates" for studies or go to pubmed.com). Krauss discovered that LDL comes in different sizes, and that small LDL are associated with high risk of heart disease, and large LDL associated with low risk of heart disease.
Further, Krauss found that a high carb diet lead to small LDL (as well as high triglycerides and low HDL). Low carb diet lead to large LDL (low triglycerides and high HDL).
So a low carb diet appears to be heart healthy in Krauss' model of heart disease (in contrast with the high carb advice from Am. Heart Assoc.)
I took out sugars and processed carbs from my diet. Dropped weight, and feel the best I have in years. Am using recipes from Leo Galland's Fat Resistance Diet, which are really fantastic. Only time will tell if my changes will help, but feeling good now is certainly helping my spirits.
Good luck! If you have other questions, feel free to contact me.