Red wine has a lot of components, some of which have health effects. Google this phrase: "red wine health benefits study"
Wine polyphenols, especially resveratrol, anthocyanins, and catechins, are the most effective wine antioxidants. Resveratrol is active in the prevention of cardiovascular diseases by neutralizing free oxygen radicals and reactive nitrogenous radicals; it penetrates the blood-brain barrier and, thus, protects the brain and nerve cells. It also reduces platelet aggregation and so counteracts the formation of blood clots or thrombi.
IN MODERATION!!! (even the non-alcohol versions)
I will point out that alcohol is a poison, but so is hemlock. But hemlock in small doses is therapeutic. ( hemlock has sedative and antispasmodic properties but was used by Greek and Arab physicians for a variety of maladies including joint pain, current uses include relieving asthma, bronchitis, cramps and joint pain.)
I have gone off the deep end with the references to using alcohol to relax one's anxieties and inhibitions. I do not presume to put that onus on you, but having written this essay, I put it out there just in case anyone who reads this might benefit from it.
Alcohol itself has erectile benefits in small amounts (large amounts have an inhibiting effect). Opening up capillaries is one and reducing one's mental reservations is another. Only you can decide if a drink is or is not beneficial for you.
For lowering one's mental or physical hurdles to erection or libido, alcohol's abilities (and to increase them, as well) are well-known. Whether one chooses to use alcohol, self-hypnosis, marijuana, psychotherapy or any other means to improve ones sexual performance is up to you.