Whatsup bro,
I am around your age and had been dipping around the same amount of time as you. I'm on day 25 and to be honest its still a REAL struggle but I'm getting through it one day at a time.
Here's some advice, this is what I do when I have a bad craving. You said that you had tried to quit for your family and girlfriends, believe me I did as well, it doesn't work. I've read on this site that you have to quit for you and only you. Well I'm not sure if I entirely agree with that. When I have a bad craving I imagine my future family, my future wife and my future kids, and I imagine having to sneak off every hour or two to throw a lip in, which is not the type of husband/father I want to be. Wherever I am whenever a craving hits I visualize my future wife and kids around me, and think about how much I don't want that around them.
That has been working so far.
Stay strong