I eat clean, don't drink, don't smoke, no recreational drugs (aside from AAS), my blood tests always come back good, I train my ass off, and I always feel pretty damn good.
About a week ago I was diagnosed with moderate cardiomyopathy. Not everything is what it seems just because you don't feel bad. Some stuff doesn't show up without VERY specific testing.
Now to be fair, in retrospect, I think this was a long time coming, as I have only been using AAS for about 3 years, but it can creep up on you. We were both young Marines once, and I think some of my habits from then caught up to me as well.