Hi, my name is Emily and my husband was diagnosed with cancer in 2011, we're currently going through treatment for a relapse. Unfortunately what you're experiencing is really common. I feel lucky that my husband hasn't been like this, but I know plenty of women who have gone through the same thing with their partners. I belong to a facebook group 'Caring for Husband's with Cancer' (really recommended- it's a really supportive and active group) and this is one of the most common topics.
The causes of this change of demeanor vary, but generally relate to the disease process itself, medication or poor coping mechanisms. (I blame the 'boys don't cry' mentality- for people who believe this anger is the only 'acceptable' response men can have to trauma.) It might be worth discussing it with your husband's doctor, particularly if it's really out of character. They may be able to pin point and address the cause. I'm guessing you're in Australia? If he's being treated in a public hospital your partner should be eligible for some sessions with a hospital Psychologist (if he consents to see them....) and you may be eligible for some counselling sessions with the hospital Social Worker. The Social Worker may also be able to link you in with some practical assistance as well.
There is help out there, and you are not alone. love and hugs, Emily
