Thanks Jennifer, Pegasus and Chris.
She is already on antidepressants but despite suggestions of seeing a therapist she never does take the leap. She does seem a lot more forgetful lately, but just forgetful, not like the complete change of dementia.
Thanks for your replies though. In therapy I really find it difficult to talk a lot of the time, and especially when it's around certain topics. Like I would definitely avoid any words around these topics because they're ... sensitive? or like vulgar or something? anyway, talking about them aloud feels too vulnerable/intimate at the moment so it helps to get feedback in another space.