I have 3 close friends who have been sober more than 20 years- 1 became an alcoholic (also smoked a ton of pot) the summer going into our junior year in HS, has attempted suicides, did a stint in rehab (maybe a month?) came back to school and has been faithfully following the 12 steps and attending meetings for 28 years. She struggled a bit to find her way career wise- she likely had a learning disability - but she did end up finding her way with a stable good job. She recently married the man of her dreams- had an amazing wedding & just quit that job to open her own biz. She is living happily every after.
Another friend became an alcoholic in college. Woke up 3 states away on Sunday with no idea how he got there or what he did the night before. He was losing friends, lost a fraternity office, and a close friend finally told him straight out that he was a drunk & no one liked him anymore, he was a crappy friend & unreliable. He found AA, started going, stayed in his Fraternity somehow (crazy) and graduated on time. He's been sober ever since. At 42 he completed an MA at Georgetown. Has a great house, nice husband & son and is happy. I posted a letter he wrote to his son last year about why he is sober.
I have another friend who became a cocaine addict (he was always a wild child; partier) at age 27-- with a wife, an ill 1 year old and a brand new baby. They lost everything, including the home she inherited free & clear from her late mother. His parents took her and the kids into their home and sent him to rehab. I don't know the whole rehab story- it was kept quiet, all of us thought he was working out of state & his parents were helping his wife with the kids since the toddler was so sick. They lived with his parents for about 2 years, he slowly rebuilt his life, got a job, bought a house, had another baby. Bought a huge house. I know for a long time that he didn't drink- but he is drinking now. (20 years later ) i assume in moderation but I don't know. He has been very successful & they lived a nice life. They divorced about 2 years ago, both of them remarried others last year and their 2 older kids are in college, youngest just started HS. I assume he is still drug free- I think he cheated- and I don't think the divorce had anything to do with his addiction, fwiw.
So -- there you go. There is always hope. There are many success stories. I know quite a few adult friends who don't drink because they had a problem before I knew them. I don't know their stories - why, what and when- but they are living successful, low key, sober lives and have been for years.