I think it depends on how close to the rest of the group you are and want to continue to be. I think excluding one person (even if you have your reasons) has the potential to cause awkwardness amongst the group. As the person causing it, this might lead to negative repercussions for you (depending on how close to the others she is)- e.g. you might be seen as being petty or trying to engineer a general exclusion of one person who you have appeared to be able to rub along well enough with for a long time. It does seem like your tolerance was a pretence, so what else might you do later along the line to someone else? Not saying that IS your intention, just that it could be perceived that way.
Excluding one member of the group may also lead to a change in group dynamic- again that may or may not be to your detriment, depending on how close to you the other people in the group are, when compared to her. Or how they feel about excluding people. It’s a risk, but how big a risk is largely dependent on the strength of each relationship.
I think that if you have a very small wedding, you might be able to blame it on numbers. But you would have to keep your discussions about the wedding in the group chat to a minimum, or you’ll be rubbing it in her face on quite an obvious and unpleasant way.
In general, though, I agree with YoniAndGuy- you may not be close with this woman but you have maintained a quasi-friendship with her via the group and have not expressed your feelings about the past. To then exclude her alone from the group could be seen as vindictive (even if not your intention). As you chose not to deal with how you felt about her actions at the time and since then have chosen to remain in contact- albeit with a distant friendship on an individual level, but a closer one as part of the friendship group (if I have read it correctly)- it does run the risk of coming across as though you’ve been “keeping your wrath warm” and have now got an opportunity to make it known. You should probably have kept your distance or continued to honour the decision you made to maintain a friendship of sorts.
It would be fine not to invite her in other circumstances- if you weren’t in a friendship group- but excluding one person does come across as unkind. It might be more palatable to your other friends if they knew how you felt about her- do they?
If I put myself in the position of your mutual friends, I might understand your reasons if I knew about how you felt about her- but if I didn’t I’d probably think you were being unpleasant and trying to play queen-bee by excluding her and that would negatively affect my perception of you.
If I did know how you felt, it would be more understandable- though unless she’d done something actively horrible (as opposed to not being as supportive as you’d have hoped) I would still think “why make it an issue now, after all this time, and keep a pretence of friendship of sorts?”. I’d feel a bit awkward about the situation and would be a bit irritated that it would be likely make group meetings with you AND her difficult going forward. Which changes the group dynamic quite a bit and make it all a lot more effort to get together.
You run the risk of you being the one left out, as you were the one causing the issue. So we might see you individually, but group meets might fizzle out.
Think carefully- if you really cannot stand to have her there, then don’t. But if you do that, you need to be prepared for the awkwardness that is likely to follow. Only you can decide if it is worth the risk.