I have a circle of about 7 college friends that have kept in touch for the last 15 years. We all live in different cities and get together every 1-3 years and will regularly send group emails to give updates about life off facebook. Of those 7 friends, 5 of those girls I consider to be my nearest, dearest and oldest friends. The other 2 girls, I will call Molly and Jen, I see only when the entire group gets together and we have never gone out of way to get together when the whole group wasn't getting together.
The first wedding in the group happened about 12 years ago and she invited the entire group of friends, most of whom were single at the time. Since that time, everyone has always gotten an invite to each other's wedding- I am the 6th out of the 7 of us getting married. Though she can be fun in a group, Molly has a very biting personality and has made some very rude comments to me. I was invited to her wedding, but could not attend. Jen is sweet, but I've just never been close to her. I really do not feel the need to invite them to my wedding. I've run this by 3 of my other girlfriends from the group that are married and they all say that they had similar thoughts about members of the group, but ultimately all decided that they needed to invite them to their weddings because feelings would be hurt.
Our venue has a max 250 capacity and we are forced with having to make hard decisions about who or who not to invite. Inviting Molly and Jen means that I can't invite 2 of my guy friends associated with this college group who I have been much closer to and would much rather attend my wedding, but certainly would understand if they were not on the list. Do I need to invite Molly and Jen?
ETA- I should note that all of these people are either married or in serious relationships so they will be invited with guests.