He definitely shows some drinker traits. The problem is discovering if he has to have it, or if he just did it in response to depression. Neither one is exactly healthy, but the person who depends on it to get by tends to be the alcoholic.
Alcoholic or not, drinking too much greatly interferes with a healthy daily life. It is something to keep an eye out for, because of your children. Alcoholics tend to make bad choices. My dad drove all the time while drinking. We were in several car accidents, one of them quite serious. The shows we were allowed to watch because of his bad judgement were disgraceful.
Just keep an eye out, and listen to what your kids have to say if he ever picks them up for a visit. If there is a drinking problem going on, it's kind of easy to spot once you're aware.
