I always thought it was a felony to shoot while drunk. I don't want to keep anyone from having their guns, but I might mention this to the guy who was shooting toward my property. Or you could ask him to pay for the damages done (nicely), and if he hem haws around, you can suggest that you would be OK with filing a claim against his Homeowners insurance. But let him know that you know of an insurance agent (I am) and they told you that most claims are not appreciated by insurance companies, and denial or cancellation would be possible under the situation. Then as you all are discussing the "problem" you could come out as the peacemaker and say, something along the lines of " Well, If its all the same to you, I would be willing to forgive the current damage, but I need you to respect the bullets you shoot as you are responisble for the bullet from the time the primer lights the gun powder, until the bullet stops. When it crosses the property lines, it becomes a problem,and my property gets damaged. I am not comfortable with that."
In any rate, as has been mentioned, it is not a good situation to be in.