Alcoholic although widely used is not actually a medical term. There is substance abuse, and there is substance dependence, the latter being the more severe.

The way you are drinking definitely qualifies as substance abuse, even though it may be socialy acceptable at your age. Whether you will eventually stop this drinking pattern and be able to drink socially is another question. Some people are able to drink to excess in college and then just "Grow out" of it and become social drinkers, other's can't, and experience increasingly severe levels of negative consequences as a result of continued use.

You're clearly drinking above the safe drinking recommended guidelines, the fact that your behaviour changes when you're drunk, the fact that you started drinking at an early age, the fact that you are already psychologically dependent on alcohol for certain activities (sex) all suggest that you may have a more serious problem that some people call alcholism.

One common definition of addiction includes the following three traits.
1. Inability to stop using despite repeated attempts (I don't know if you've ever tried to stop drinking)
2. Increased tolerance - needing to use more to get the same effect. If you're blacking out, I suspect tolerance is an issue for you.
3. Continued use despite negative consequences. Have you had any negative consequences from your drinking, ie grades suffer, offending friends, being injured in fights, not likeing how you act while drinking.

I would worry less about what labels get attached to your drinking and worry more about how drinking is affecting your health and your life. If you do decide that you have a problem with alcohol, then better to quit drinking while you're still young, before you get worse and develop physical dependence. Addiction only gets worse and harder to quit the longer you're in it.

Why not try not drinking for a month and see how it goes. If you can't stay stopped for a month, you definitely are addicted.

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