I hear your pain and I guess I have been very lucky. First, I used to be a WordPerfect fan but obviously that is lightyears ago. Because of my utter frustration with the office's Windows-based Office 365, doing exactly what you say your Mac version is doing, I chucked out their Windows PC and went the Mac route. I have really had minimal problems with Office 365 Mac. I often have huge and complex Word documents to deal with that would just simply crash on the Windows PC. Were it not that it was the office's official issue, I would have kicked it off the desk a long time ago.
Lately when colleagues ask me why I don't walk around like a man possessed anymore, I point to the iMac on my desk and continue my work, with a much lower blood pressure. I have Office 365 running on three other Macs with no issues at all.