Most historical fiction novels seem to portray George as hating Jane Parker, is there any real evidence that he detested his wife so much? Did his affections belong to another woman? Or did he just lose interest in her (assuming he had any to begin with)?
I'm not sure why George Boleyn is always presented as hating his wife and Jane as a jealous and spiteful woman who grows to hate her husband. There is no evidence either way. Some people believe that the fact that they were childless is evidence that they were estranged but it could also mean that Jane had problems conceiving or that George had some kind of problem.
Jane's biographer, Julia Fox, says of the marriage:-
"Her marriage was successful and there is no reason to believe it anything other than happy. Love matches were rare but they could happen and they could certainly develop." p120
Jane was one of Anne's ladies, one of her inner circle and close enough to Anne for Anne to tell her of the King's sexual difficulties and close enough to George to pass this information on. There is also evidence that she sent Sir William Kingston, Constable of the Tower, a message for George, saying that she would "humbly [make] suit unto the king's highness" for him. However, there was nothing she could do to save him.
So, it is not known what their married life was like and there is no evidence that George 'strayed' or that he did not love his wife. Some people believe that George Boleyn, Dean of Lichfield, was George's illegitimate son but if he was then surely he would have been the heir to the Boleyn estate on Thomas Boleyn's death in 1539, rather than Mary Boleyn.