Syngin seems like someone who doesn't know how to have fun without alcohol; Jovi seems like someone who doesn't know how to experience a day without alcohol. Syngin may or may not be an alcoholic, but there's no question to me that Jovi is. Who gets a morning drink at the airport after you get off the plane?
Unfortunately, that level of drinking is normalized in his social circle, so he doesn't have a clue that it's dysfunctional. But he's going to have to grow up in fast-forward (much like Jihoon, except for the gainful employment and the booze). If he can do that, he and Yara may work out as a couple. If he can't, then I'm not very hopeful for the long term.