One should really get tested for B12 and Vit D. Along with magnesium, these are the BIG three for re-establishing healing.
Alcohol is a diuretic and over time would really deplete magnesium. SlowMag or a chelate daily would help in this regard. Avoid the oxide form, as it remains in the bowel and does not get absorbed into the blood stream.

You would calculate how much Vit D to use from the test results.
1000IU D3 for every 10 points to raise up to about 50.

Many people in the US are quite low in all three of these nutrients, even if they don't drink.

If you are hypothyroid, you may not be converting betacarotene properly in the liver. This is dependant on T3 levels. So taking a Retinol form of A, extra may be helpful. No more than 8000 IUs a day. Many good multivits have some retinol in them. So read your labels if you use one. They have a mixture of retinol + betacarotene.

Most recovering drinkers do well on a balanced B-complex.
B-Right by Jarrow has a good formula to try. I'd still use the B12 separately however.