Hi suzynewt
You probably have very mixed emotions right now. The diagnosis will enable you to access the right support. The brain scan confirms the type of dementia - whether its vascular dementia or Alzheimers then the right meds can be prescribed. I do think when they have memory tests that they fee anxious, under pressure, clam up and words don't come out.
My MIL was diagnosed just over 12 months ago and on reflection it came as no surprised based on her behaviours and poor memory. She doesn't remember that she has Alz and becomes anxious, stressed, upset when its mention, so we just refer to her memory problem as she openly admits her memory is terrible.
There are a number of useful fact sheets and info on this site as a starting point, but the folk on here have so much practical and emotional experience and are very willing to share. Just keep posting, asking questions and rant if you need to... we all need to at some point.
We were referred to the Alzheimers Society and whilst the advice and support helped us understand this awful illness, MIL really did not want to be there as she says she's ok and doesn't have dementia which is so far from the truth!
Oliver stone's book 'Contented Dementia' also helped me, but like any self help book you pick and choose what you adopt and changes you make. There are some TP'ers that don't agree with sone if his thoughts but its worth considering.
keep posting... its a journey and not an easy one. I'm sure others will be along soon with words of wisdom.