She also believes the senior royal has a "desire for approval" and a "short fuse" when he is provoked.
Speaking to the Daily Mirror Online, Ms Myers said: "Prince Philip’s handwriting indicates a writer with a good intellect who tries to exercise numerous built-in controls over his strong depth of feelings to keep him compatible.
"The angular writing denotes a critical and somewhat forceful personality, having strong likes and dislikes.
"He likes a challenge and can inspire others with his initiative, high standards and enthusiasm, his creative ability with artistic leanings helps him to accomplish and achieve goals with zeal and fervour.
"However, he has a short fuse and when provoked can retort with caustic comments.
"Anxious to maintain a good image he appreciates the importance of his role in life having a desire for approval.
"An individual personality he may show indifference to conventional commitments and is unlikely to change an opinion or decision even in the face of logic or reason."
Ms Myers added: "He does not always face up to problems and will find excuses for his actions by denying difficulties and rationalising by avoiding them and thereby his conscience is clear.
"Sensitive to criticism although hurt will go his own way. It is difficult for him to forgive past injustices.
"Prince Philip can relate readily to others but in reality he can enjoy working alone and is happy in his own company selective in his choice of friendship.
"Lover of good living he enjoys luxury and quality appreciating and enjoying deeply all that influences the senses.
"Although he is communicative he keeps his own counsel and his conversation will be guarded as he is able to conceal pertinent facts he will be secretive and thus able to skirt issues."
Philip blamed the cause of the crash on the “low sun,” despite the fact Ms Fairweather later stated that the day was overcast.
However, the injured woman – who was travelling with another woman and a nine month old child who were both unharmed – told told the Daily Mirror Online: “He’s tried to give an explanation so I appreciate that, whether I agree with it or not.
"It is a difficult letter to write – to know what would be the right thing to say without making me more upset.”