Hi CJ
You may be interested in the DWP page below.
Anxiety and Agoraphobia in people with hearing disability My understanding is that if you suffer from anxiety or any other mental illness as a result of deafness you can score points in the mental health test. But social isolation on it's own, as a result of hearing problems, may not be considered a mental illness.
Evidence from your GP to confirm a diagnosed mental health problem would be useful when you claim, as it is not unknown for an ATOS HCP to only apply the physical test to a claimant that has mental health issues as well.
Good luck when the time comes
Derek