How do you do it? Well, for me it needed me to accept that I am an alcoholic and that I can't reliably ever take 'just one drink'. I'd had plenty of half-arsed failed attempts at cutting down or whatever before the time that is my sobriety date by the way.
When I finally did get sober, a big part of this was accepting that alcohol makes my life unmanageable in various ways: I didn't perform well on my job, merely doing the bare minimum and always in a state of stress and resentments about it; I was emotionally unavailable for my partner and family; money problems due to bad spending while drunk and to cheer myself up when sober; other compulsive behaviours that I won't go into on here that could be damaging to my reputation, professional status and relationship; my home was a a dirty, chaotic, pigsty; and other ways that generated a mix of shame, self-pity and anger, which I'd always reached to alcohol to sooth the pain of. But finally I acknowledged the cyclical nature of my problem but I was still drinking. Then something happened and I reached a slightly new low. But. 'slightly' or not, it made me realise that I HAD TO CHANGE. Me. Nothing or no one else. ME. Because what I hated about my life was ME. Who I had become. And I couldn't change that while I was still drinking. I found myself feeling that special kind of desperate which gave me the willingness to start to try things that I hadn't been prepared to do before. Like stay sober. Like join this forum. Like go to AA. And later, when I realised that AA is about more than drinking coffee and chatting, and those desperation levels started raising again (because I wasn't really working on my sobriety on a personal level. Not really ) I did one of the hardest things I have ever done, and asked someone to be my sponsor and committed myself to working the 12-step programme with their support. Hard maybe, but I maintain that I learn more working those steps than I did at 4 years doing my degree and postgraduate course at the University of Cambridge. And it has had an even more positive impact on my day to day living as well I reckon.
Anyway. That's my journey so far. How YOU do it will be down to your own acceptance and your own willingness, and what you choose to do. Your thread so far already kind of smacks of someone who hasn't really accepted the impact that alcohol has on his own life and on his family and partner (because, I'd bet that she'd happily not have that drink if it would help you to stick to sobriety yourself ) and you sound like you're asking how you can stop drinking, but have already disregarded anything that will involve outside help. That's not willingness.
When you want to get sober more than you want to continue as you have been doing (not just because at this point in time the getting-away-with-it magic seems to be a little off-kilter), then you will find yourself willing.
When people talk about rock bottoms, it's important to remember that rock bottoms look very different from each other. We don't have to lose everything. I only lost my self respect, my sanity, and any sober friends I'd had. I still kept my home, my job and my partner, but I'm sure that given more time out there I'd have started to lose those one at a time as well.
I wish you well in your sober recovery.