Obviously, this is not medical advice, but it's doubtful that you ruined your body. As many here have confirmed, the body tends to be quite resilient and can make great gains once you begin treating it right.
Case in point, in my nearly 2 years of sobriety, I've dropped 50# of fat and packed on 10# of muscle. I've competed in power lifting events, got back into mountain bike racing and skied some awesome double-blacks out west - and I'm in my mid 50's!
There's a great thread on this forum where a bunch of us gym rats and fitness buffs humble brag about our workouts. It's a great support resource and just an overall enjoyable place to hang out!