Moving to In design.
What is the exact version of InDesign you're using?
Do you have any extra plugins or a font manager?
(Note this is a user-to-user forum, with some very knowledgeable contributors – not me! – who, I'm sure, will sort you out.)
I'm using ID 2015 for Mac. And yes, we have used a font manager (Suitcase) for many years.
The latest version in CC2015.4.1, though some are reverting to CC2015.3 because of issues with the latest version.
I wonder if Suitcase is causing your problems.
Hang on for a bit and someone with more knowledge than me on this matter will probably chime in with some suggestions.
What is your EXACT version? Go to ABOUT to check.