Okay, I read "Forever War" and then "Forever Free" by Joe Haldeman....
"Forever War" was a fine book, though it felt a little anti-climactic. Not a bad read.
"Forever Free" was frustrating. Learning about what this universe had evolved into was cool, but at a certain point the plot veers off into mystery territory, and the resolution/ending is very sudden and deeply unsatisfying. Some people will like this book, but I was disappointed in the end.
Now to pick something new...