Rostrevor is a nice little village on the loughside and there's a pub there The Rostrevor Inn that does food as well as accommodation.
Warrenpoint is also an option, but is a sizeable town and might not suit you, but the Lough and Quay does rooms and food.
Carlingford is a beautiful medieval village but is fairly expensive and usually completely booked out at weekends but you might get a deal on a mid-week stay. PJ O'Hares in the centre of the village is great for food and drink.
I have never stayed in any of these I should point out. But I live only a few minutes away from Carlingford and have often eaten in O'Hares so can definitely recommend it.
Drop me a pm and I'll sent you a waypoint for one of the best views of Carlingford Lough and South Armagh and if you want a scenic ride in the area I'll do a route for you.