I often do a lot of things when I'm drunk and some people find that they can better express themselves when drunk.It don't mean nothing.But in your case, I think that you are feeling for him more than he is feeling for you. He could have just responded to the attention you gave him and felt flattered.
I don't think you should hold anyone who is drunk to their word. Sometimes, it does happen that a person will give you the looks, the stares and underlying actions of being interested.
And then, when drunk, they can just pounce at you. The following morning they get all shy and timid about it- because all their feelings are now out in the open: That's different.
This situation sounds like nothing I've described.
You've liked this guy for 5 years???? It's likely you have been "friend zoned" and he may not see you in the same light.
If you feeling brave- state your case and put yourself out there. I mean , it's been 5 years.
Or you can just brush off the drunken stupor as exactly that...a drunken stupor!