Friends don’t like my girl. Advice?

[MaCruz]

So back in 2005 I had these two friends (a couple) who hung out with me a lot before I started dating LeAnn. Once we started dating, I saw them less often, but we all still hung out together on occasion.
However, after LeAnn and I had been dating for awhile, they invited me to dinner and proceeded to tell me how LeAnn was not good for me etc..

As you can guess, LeAnn did not take this well, especially since they flat out refused to talk to her about the problem when she wanted to just meet up and talk about it.

In 2007 we went to a wedding in which everyone was invited and my former best friend pulled me aside during the reception to talk to me regarding the whole scenario with me, friends, and LeAnn. During the long conversation in the heat.. LeAnn was left alone to be entertained by my friends, and I missed most of the reception. I thought that was messed up because my name was called and I wasn't there.

Ultimately, they don’t want to hang out with us anymore and generally if one of us is attending a get together, the other will not. Which really sucks for our mutual friends.

There is an upcoming birthday next Friday with my other best friend which I have not seen in months in which we all seem to want to attend, but it is not going to be very comfortable. I know this is not high school, and we are all grown adults but what should we do?