I guess from the opposite aspect at my own wedding my older brother was there. My wife April and him were together for over 3 years. Their relationship had been very sexual before they broke up because my brother had started messing around with a girl he worked with. In reality theirs was a young love and those rarely last when you are such young teenagers, but he was there when April and I got married.
My brother and one other guy from our hometown were the only local guys to have fucked April back then. The other guy was her older brother's best friend and he was there at the wedding too. I didn't care. I was marrying the most beautiful girl in the world so I felt like I had won!!
My brother and I were always close, but I could tell that my dating April at first bothered him. I think he regretted how he just destroyed their relationship. They are friendly and talk in the necessary family get-togethers, but you can still sense the betrayal April felt when they broke up. Those emotions made it tough for me to break through to her and I had to prove I was different from my brother, even though she and I had been very close friends since we were in kindergarten.
At the time of our wedding she really wasn't speaking to my brother again yet, but I couldn't very well NOT invite my own brother to my wedding.