Story time! I was sitting on a night bus once, traveling from Göteborg to Borås. As it was pretty crowded a Swedish couple, having been out partying, shared a single seat next to me and struck up a conversation in English. After a while I proudly claimed: "Oh by the way, I know a few words and phrases in Swedish". "Really? Say something!", said the boy. I wanted to remark on the slight drunkenness of my conversational partner and went "Du är ful!" (meaning to say "Du är füll!" ("You are drunk!")). "Wow. That's a rude thing to say, you know that?", said the girl jumping to the defense of her boyfriend. Still not noticing my mistake I argued: "But it's true! I mean, just look at him!!" .... Anyway, we managed to clear up the misunderstanding and had a big laugh at it. Swedes are cool. :)
Yes I think if I ever had to speak Swedish and use the proper word for drunk, I would just say a different phrase. Du drack för mycket. And follow up in English with You seem drunk. Because even quite inebriated Swedish young people most likely would understand me in English. I don't want to risk insulting a drunk person. Even when we mess up, people appreciate that we try to speak their language while in their country. And being polite, they won't correct us either. I spent an entire trip saying "devil" for Gävle, the name of a beautiful town. I came home and my father corrected me but he could have said the town's name a thousand times and I would not have heard the subtle difference between correct and calling the place "devil". In his generation, unlike here in the USA, the word devil in Swedish is a major swear word. And of course, the difference between the town's name and "that" word are a totally clear difference to natives speakers.
I'm guessing you said djävla for Gävle, since that's a major swear word. It means "damned", though, rather than "devil." The word for devil is djävul, and it is not a swear word.
The initial d in those words is silent, but it's not just the vowels. Swedish is a pitch-accent language, and the pitch is different between Gävle (start high, move down) and djävla (start low, move up).
I like your idea of saying "Du drack for mycket." When I was practicing my Swedish skills, visiting Sweden for the first time, I did use the Swedish word for drunk, when my Swedish friend was hiccuping. I think I pronoounced it correctly 'cause everyone laughed.
Oh, but about the world "gavle" there is a song titled "en gavle pa karlek" by GES. So is the translation "A devil of love"?