I watched a movie on TV, about an elder brother going to his younger brother's wedding. He's kind of a tool and starts running it all.. Though it turns romantic as the story progresses and the girl he once liked is at the wedding. I don't really remember, but I think he gets visits from three "ghosts", kind of like the usual "Three ghost visit at night"..
They end up together in the end, and he stops his younger brother's girlfriend from leaving in the end.
Please help?

Sounds like "ghosts of girlfriends past"

Agree with confuzed1978 - definitely sounds like "Ghosts of Girlfriends Past" with Matthew McConaughey & Jennifer Garner.

http://www.imdb.com/title/tt0821640/