People often end up with their mothers and/or friends and/or books and web sites with traditional formal ideas about wedding invitations helping them with details, as the couple themselves are often a bit overwhelmed by a mountain details on top of an already momentous personal event.
And, times have changed, but weddings are a ceremony where many people still like the traditional forms, for various reasons. And in the not-too-distant past (e.g. 50 or so years ago), the mainstream traditional way of many/most people was to refer to married women as Mrs. [husband’s name]. And even a mistake not to do so.
I know people who were annoyed with each other for years over the wording of various things on wedding invitations!
It seems to me it’s very much not worth it to get annoyed about… but that the annoyance points to something else in the annoyed person’s feelings and ideas and personal history that could be worth examining, to heal whatever old wound that is, if such skills are available to that person (in this case, the asker of this question).
So my suggestion would be to forget about this present wedding invitation, and to feel what the upset about it feels like, and ask yourself (ask the feelings in your body, not your thinking) “what is this upset really about?” And sit with and reflect on that.
And then, also ask yourself where this feeling comes from. Try to remember when you have felt this way in the past. When was the first time you ever felt this way? And then ask what that time was all about for you?
Ask yourself how genuinely relevant those feelings are to the situation where someone used the traditional formal format for the wedding invitation from your long-time friend. Are you really upset about that wording, or did it just open up this unhealed lifetime pattern of upset?
Then sit with all the painful feelings you’ve had from this whole pattern. Mourn for the actual upset of the original event. Mourn for all the inauthentic upset it has caused since then. Recognize it as a trigger you have, and a way of thinking that may sometimes lead to upset when it gets triggered in situations where it may not really be what you want to respond that way.