Hi Greg.
I use apt-get and dselect for package management..one reason aptitude wanted to remove packages I did not want removed..sound kind of like your situation.
Yesterday I used aptitude in a virtual machine and have to reinstall gimp and freecad
If you do not mind trying apt-get and seeing if it behaves more to you wants. I never figured out why apt-get & aptitude differ in this regard.
Today on a real machine I used apt-get and only g++ (plus its dependencies) have been installed, nothing to reinstall.
Thanks for the hint.
Rolf