Ok well.... I could not find a direct way to update grouping as I updated my items. However I found a work around.. I implemented a event that is fired whenever I change text within the text box, inside the event and after some validation I call the refresh() method on the collectionview and the grouping updates.
This solution I kind of cringe over because calling refresh will call the textbox changed event for each textbox being refreshed, just numerous unnecessary calls to that event that goes through my validation within that event. So the more textboxes I have, the more times the event will be called whenever i refresh the view for a simple text box change.
If anyone else has any solutions or ideas please let me know as I am going to have to stick with this solution for now :(
EDIT Pseudo-code solution if anyone is curious...
When textbox gets focus, set a editing flag to be true, so no transactions on the textbox can happen during editing.
When textbox loses focus set editing flag to be false, check to make sure the current text is different from the previous text.
if the current text within the current textbox is different refresh the collectionview object