I don't know if it makes a difference but my alcohol of choice was beer and I consumed between 10-15 every night for around a decade. I still would consider myself an alcoholic because if I drink even one beer, I am going to keep drinking until they are all gone, but I guess I have the ability or wisdom to choose not to have that first drink, or maybe I'm just co-dependent without anyone to make it happen. Lucky for me I suppose.
So first beer has an effect and you can make the decision whether you want that effect (with its pros and cons) or not. But if you say yes, then there is less reason to say no to the 2nd drink. After 2nd drink there is even less reason to say no to the 3rd and so on.
So when you contemplate taking that first drink ask yourself: If I do, is there any reason why I wouldn't keep on drinking after this first drink? And by the logic above, there really is less of a reason to say no to the 2nd drink than the first and so on.
But curiously and luckily this logic means that there is also a big reason to NOT have that first drink, because you can assume that its effect is not only the effect that one glass has on you, but also the effect that it makes you drink more. That is a good reason to not drink the first drink. If you don't say no now, why would you say no later?
So I wouldn't consider you an alcoholic just because your first beer leads to the 2nd and so on. You are not alcoholic you are just being logical. If you have a reason to drink the first beer then you also have a reason to drink the 2nd and so on. But luckily because you are logical you can see that it is not a good idea to drink that first beer in the first place.