Voices: My wife is changing, seemingly without reason – could it be dementia?

Dear Vix,

I’ve been with my incredible wife for almost 20 years. We met later in life and already had our own families, but over time we’ve become one. My wife has always been an avid and talented swimmer, competing in competitions around the world. Her mind has always been razor-sharp too; she’s full of wit and kindness, and is certainly the joker of the family, but recently she’s been changing – seemingly without reason – and now I’m fraught with anxiety and worry for her.