Some reasons.
1. I'm 37 and I saw the direction I was heading(it was ugly). It was a vicious cycle and I kept on repeating it and I honestly wasn't going to see 39-40 the way I was going. I was drinking a ton pretty much every single weekend. It was time to get healthier in general.
2. One of my best friends passed away mid-October last year and he was also an alcoholic like myself. He was also 40. I attended his funeral and I made a pact with myself that I wouldn't put my dad, my girlfriend and friends, and my brother and his family through attending my funeral. I want to lead a productive life and so I decided to put it down,
3. Lost too many great jobs and putting my dad through sending a son to another rehab was a "get your ******* **** together" moment for me. I should have gotten my **** together many years ago but I didn't. My dad is near 80 and should be enjoying retirement, not having to be by the phone in case I call for whatever reason from a treatment facility. I had to take full responsibility and ownership and I'm trying to correct that every single day.