It really is a fairly simple thing, you need to look and see if you are just "venting" here with the posts, or if you are really unhappy. In the end if these people are your friends they will allow you to still hang out in vent/mumble, keep your alts in the guild(maybe even raid with them on your alts), and go on with your friendship. If they react negatively and kick you from the guild, ban you from the voice chat server, then they weren't your friends in the first place. It is all about balance and in the end what is it that makes you keep coming back? The raiding or the people you are currently playing with.