I always use it without logging in ‡, and make a point of starting each fresh chat in a fresh window so its perspective in one conversation isn't tainted by some random line of thinking from before. Can't stand when it makes assumptions about my intentions because I mentioned having kids before, or had talked about a different property or venture or whatever.

‡ I'd tried logging in recently and immediately it started nagging me to upgrade. Went back to using without an account and bizarrely the situation is far better.

It is not necessary to logout for this purpose. It is trivially easy to disable the memory feature permanently. There is an easily available toggle for it.