Why do men often get so defensive/mad at the littlest thing.... I've been going through it for 9 yrs?

with my husband and now it's coming out in his performance reviews/leadership program for becoming a manager at his office..... even through he knows it's an issue he is still doing it to me.... what is his problem? what's behind this irritating behavior? I am the oldest and most ambitious in my family whereas he's the baby of his family.... I know he gets frustrated about his job but I'm like "if you don't like it, look for something else" -- I have always said to him that I'd support any additional education he wanted to get, etc.... I am at a loss... I hate having to walk on eggshells all the time etc.... I am very patient/have put up with lots of **** in my life and that's why I make a good income now.... why can't he be more patient, at the very least with me.... I made dinner tonight (which I rarely do during the week) and he ruined everything because of something little... I told him how to use a certain cookie sheet so the stains don't get baked in..... why is he like this? he's like "I don't know what purpose I have in my life.... just to suffer here with you...." -- I'm sorry but I am a very sweet person... could it be because he's Muslim raised in Pakistan, etc. while I am Pakistani Christian... I am pretty devout and am happier because of it... I see one of my purposes in life, to worship God and make a differencde in this world.... my husband needs God..... at least with Christianity there is hope.