Alcohol kind of creeps up on you over time.
I was in Greek Life in college. I don't regret a second of it, but the drinking culture was omnipresent (we did have dry brothers but if you drank you drank).
After college I moved back home. I had a few concerning episodes that one could "pass" as a mildly embarassing thing (vomiting after a comedy show once I was home, passing out during a family party). The first time my drinking came to a head was when my then-SO called me at a work retreat and I realized I had consumed about 30 drinks in the past 4 days- I was violently hungover and unable to consume food.
Several months later, we broke up, a relative died, and I came into enough money to pay off a significant enough chunk of my loans so that I could move out. During this time my therapist suggested I curb my drinking but I didn't really take him all that seriously. Dumb things kept happening- the most prominent event during this period was that I vomited while drunk gaming online with friends. Sometime after this I took my therapist's advice to quit drinking for a week. My mind cleared up a lot but I resumed after.
Things came to a head when I woke up one day after a day-long bout of drinking (I went to a tailgate and ended up going out to bars later that night). I felt like my liver was going to explode. The worst part was that I had errands to do that day and the entire time I felt like I was going to die.
I decided to indefinitely quit drinking. This was over this past November and December, and I had a few holiday parties to go to- I mostly teetotaled at them, but one conversation stuck out to me. A college friend who was older than me told me she had to re-calibrate her drinking life post-grad to function normally. I kind of realized that I hadn't done that.
I've started drinking again but I've kept it much more muted. I don't go to my local bar after work anymore. I don't really club. I never really drank alone much (the online gaming this was an outlier), so stopping that wasn't hard.
I do think there's a way to curb bad drinking habits, and I think I'm making headway in doing that, but the key is to recognize that your habits are problematic. Right now my mantra is
1) Have a predefined limit 2) Nurse the drink (I drink everything fast, so this is hardest) 3) Don't let people pressure you. Don't feel the need to drink at someone else's pace. Don't feel the need to take shots because someone bought them from the group.
I know this isn't perfect, and I'm not truly abstaining for good, but I'm in a way better place than I was before.
Don't make excuses for yourself. If you feel like alcohol is impacting you, do something about it.