Was I in the wrong?

So back in the Willy Ville days, I had a friend that I worked with at the YMCA.... I wasent the closest person to her, but we often scared our life experiances with eachother, and would hang out from time to time. Well a few months after I started getting serious with John, she was getting into a pretty serious realationship herself. Being young couples, we Spent some more time toegther, and we talked more and related more on our joint expericanes in life at the moment. I think we were getting to be alot closer as friends, but so were the Guys.....They seemed to have alot in common, it was kool, because anytime we went out we were all happy because the girls could chit chat..and the boys could do WHATEVER BOYS DO!! Well John and I moved out of WillyVille...we still hung out once or twice with this couple, but then they broke up!!! I know how devistating this was for both sides of the party. I was trying to do whatever I could to show that I would always be there for her. But in the same respect john and I continued being freinds with the guy. I didnt really see how or why I would need to ask john to stop having a a friend... (Take in mind the ONLY guy that john really bonded with while we lived in willyville) Well my friend (the girl) got incridably mad at me, and told me that I was not being a good friend...because it was impossible to support her and be a good friend while still talking to him!! I told her that I didnt feel that My friend ship with him had nothing to do with me and her...its not like I would talk to eachother about the other.... But she still told me that she couldnt handle knowing that I could have hung out with him, in a time before I saw her!!! take in mind this was not some weird 3 some kinda of thing...and also we werent in High School!!! SO what the HECK??? She told me to leave her alone from then on!!! SO I have! I tried to fight the battle...but I do want to respect her wishes of being left alone!!! Yes John and I are still friends with the guy...and yes we still spend time with him. But my question is...Was I in the wrong??? I think about this girl every so often...It really hurts my heart that I hurt her, and made her feel like she couldnt trust me as a friend!! So please tell me!! HONESTLY...Was I wrong?