Hi ipaid,
Alcohol (or almost any other drug) will affect your brain.
For very good reasons SR doesn't allow medical opinions or advice but the pathology of addiction (dopamene receptors and all that) is fairly well understood (your post indicates that you're a smart person so i'm sure you've already "googled" it)
In my opinion, and that's all it is, it doesn't carry any weight, - you ask "can it be fixed?"
well yes is the answer - but you've got to work at it.
You're only 21 so it is harder to stay away from socialising than it is for 54 year old me.
But it is easier to break a year or two's bad habits than 35 years plus
You want to drink but you know it's bad for so don't
...It's like two bears fighting it out