The problem you're running into is that a Table of Contents is just that: a table that lists the contents in the order in which they appear in the publication. This is how InDesign creates a TOC.
The functionality you describe is of an index, which does group multiple entries of the same item.
So, other than creating the whole thing by hand ("not recommended," as they say on configuration options), you really have two choices. Which one works best for you will depend on the size of the project,,but I suspect it will be the second.
You can create the TOC and edit it to modify. (Keep in mind that every time you refresh the TOC you'll have to modify it again.)
You can use InDesign's Index feature (or any of a number of great scripts) to create an index and style it the way you want. You'll have to add "Contents" at the top, but everything will stay in the right place when you refresh.