How do you stop?

I am a 28 year old male. I used to have hobbies and an avid interest in bodybuilding. I was young, healthy, in great shape and enjoying life.
Then around the age of 23 I started taking an interest in alcohol. It was shortly after I got married and was working a particularly dull job upwards of 60-70 hours per week. I started looking up new drink recipes and enjoyed having a few drinks to relax after work and before dinner.
It wasn't long before I gave up working out, gave up on hobbies and soon my only interest became alcohol.

I didn't think I had a problem because I have been drinking every night for the last 5 years but never missed a single day of work, never had a DUI, never lost or damaged a single relationship and nobody has ever noticed or told me that I drink too much.
The only real problem I see with my drinking is these few things...
1) I know I'm doing significant harm to my organs
2) I am not in shape anymore (a passion of mine that used to be important)
3) once I start drinking I don't accomplish anything other than relaxing

I have a wonderful marriage to my wife who is my best friend in the whole world. But now my wife is pregnant with our first child, and I wanna be the man my wife and my new child deserve me to be. But as much as I'd like to, I just can't give up the habit of drinking after work.
I make plans to get myself together and give up the alcohol, clean up my diet and get active again. But after my work day is thru, all I care about is relaxing with a few drinks.

I read on this forum that a single drink is categorized as 1.5 ounces of 80 proof alcohol. If that is the case, then I have between 8-12 drinks per day, 6-7 days a week.
I have a very high tolerance for alcohol and it never affects my motor skills.
But I take a lot of chances with alcohol and I drink and drive on a regular basis...

I don't want to be this person anymore.
But I'm not ready to give up alcohol completely.
How do you draw the line between problem drinking and social drinking?
How do you quit something when it's become the only thing you enjoy doing?

I'll give you a short answer -- if you enjoy doing it and don't see it as a problem yourself, without people telling you "you have a problem", you won't quit -- no matter what others tell you. This is from experience.

Hopefully killing someone while driving drunk won't be the shock you need...

Nobody has ever told me I have a problem, because nobody has any idea I drink as much as I do. I have never had a single negative consequence from my drinking. When I drink with friends I will ingest 3-4 times as much alcohol as they do and yet not exhibit one single outward sign of intoxication, while they're slurring words and have impaired motor skills.
I never have hangovers and had never suffered any lapse in memory, until recently.

The only reason I have such a difficult time not drinking is because I enjoy it so much, it's become my habit and I haven't had any negative consequences forcing me to quit.

I want to quit in order to improve my health and prevent any negative consequences that will inevitably occur if I continue in this lifestyle.

At the risk of sounding conceded, I am a fairly intelligent person. I am successful in my secular life and am very hard-working. I have always had an extremely good memory which has served me well in work situations. But lately I have had difficulty remembering details I used to find very simple.
The other day I was out for dinner and drinks with friends, and after the meal was over I couldn't remember a single thing we talked about at the table. I wasn't black-out drunk or anything. I was completely in control and well within my "acceptable range" of intoxication. But I just couldn't recall anything that had just happened.

It makes me wonder. If I am so intelligent, why am I working so hard to kill brain cells?

i smoked weed to stop drinking.
i still felt that draw to the alcohol on occasion but i would fire up instead.
it worked for me.

SMART - Self Management and Recovery Training. It's online and there are face to face meetings as well. It's for any addictive behavior.

It is abstinence based in its philosophy but does not require you to be. You are not required to have a higher power, declare yourself "powerless" over your own behavior, label yourself an "alcoholic" unless you want to for some reason, or attend meetings for life. You may practice and work on the tools they provide and eventually graduate and move on or you may decide to become a volunteer there, etc.