If for whatever reason it was decided that a couple would get married then right away get divorced after the week of Sheva Brachos (believe it or not this happens!) Can they indeed still make Sheva Brachos during the week after the Chassanah? Is there any reason why if they have decided to get divorce and terminate the marriage after these days that the actual "Sheva Brachos" can't be made?
The question wording is actually inaccurate, Halachically speaking -
make Sheva Brachos during the week after the Chassanah.
While common practise it to "make Sheva Brachos", Halachically, Sheva Brachos are said at meals after the wedding under specific conditions.
See the Kitzur Shulchan Aruch Siman 149 for details.
Essentially, in the case of 2 people who have never been married, then if there are Panim Chadashot - and it's not only close family at the meal, then Sheva Brachos are said.
Going back to your question, if they plan on getting divorced, they probably are not going to even be eating together. But if they do - and there are Panim Chadashot present - then they are obligated to add The Sheva Brachos after Birkat HaMazon.