Your concern seems perfectly reasonable. As a psychologist, I have encountered this type of scenario before and it never plays out well. Someone usually ends up with their feelings hurt. Additionally, it can lead to serious trust issues within the relationship. I would never recommend that one of my patients go and see an ex-lover...under any conditions...period. It can become a serious obstacle in the way of building a new relationship. Although your fiance may have only positive intentions, it does not change the fact that her actions will upset you. She is only thinking about herself right now and needs to consider how you might feel about this scenario. I DO NOT think that you are just being insecure. She is dismissing your feelings...never a good sign...especially coming from a woman. You should attempt to have another serious conversation with her about this. Tell her that you are uncomfortable about the situation and would only feel ok about it if you are able to go as well. If you do this and she refuses, you may have more to worry about than just one little date. If she will not honor your feelings about this, what else do you have to look forward to in marriage?? Give her a fair chance to accept your conditions...tell her that it would mean a lot to you. She is thinking about what SHE wants, not about what YOU need. Aside from my professional experience, as a husband, I would be outraged if my wife went to meet an old flame without me. I would consider that to be very disrespectful. In fact, so would my wife. Do me a favor and ask yourself this: WHY DOES SHE NOT WANT ME TO COME? HOW COULD IT BE "BETTER" IF I AM NOT THERE? WHAT EXACTLY DOES SHE WANT TO DISCUSS "ALONE" WITH THIS MAN? I think these are all legitimate questions. You sir, are not a doormat. Don't allow her to dismiss your feelings about this. Yes, it is true, you should be careful when picking your battles. HOWEVER...this is not a trivial matter and warrants your attention. You and YOUR woman need to sit down and have a serious conversation. Stand up for yourself and don't let her mow you down on this issue. It will only set up the rest of your life for this type of behavior on her part. I am not suggesting that she will "cheat" on you, but I am suggesting that her behavior seems suspicious to say the least. Take care and good luck!