Relapse is not a part of recovery, it is part of active addiction. Recovery is using all your coping mechanisms to stay sober, especially when the cravings are so strong. Regular AA meetings, not just attending but getting a sponsor and doing the 12 steps. An alcoholic that has truly accepted their illness knows that they can never, ever, drink again. Not even one.
OP, every relapse is an opportunity to access your coping skills and adapt them. Six months sober is wonderful, a huge achievement. However, stopping drinking is one thing, the next is developing a sober life for yourself. New hobbies, self improvement, exercise and so on. My DH managed ten months sober. Yes he was sober, but he was just existing, not living. He didnt want to leave the house incase he was tempted to drink. He didnt want to get a job incase he was tempted to drink. He did everything he could and should do to keep his sobriety, apart from actually living. Without any kind of real life, it was inevitable that one day the addiction would win.
DH entered rehab this morning for the next two weeks. He always hated the thought of rehab, because his brain knows fine well that he wont be able to drink. But he also knows that there is this hurdle of what comes after getting sober that he has to past.