Sex isn't about anger, saying he was angry is utter bullshit. What a bastard.
You know why it's normal and everyday now, don't you? Because he's biding his time until he does it again. By staying and doing nothing, you're showing him that he can get away with it. That's not me blaming you, not for a second, just explaining the mind of a domestic rapist. He will do it again, everything will be normal and he will 'explain' it, and you will start doubting and blaming yourself and the gaps between rapes will get smaller and smaller...
Sweetheart, your marriage is over. This man RAPED you. He has ended the marriage by carrying out a disgusting crime against you. There is not one excuse on earth for what he did. If you stay, you are giving permission to be abused again and making your children grow up with a sexual criminal.
If I sound harsh, it's because you're wanting it to not be what it is and wanting it to all go away, but if you do that, it will happen again. And even if it doesn't, this man is an abuser and a rapist and not fit to be a spouse or father. The coolness and casualness of his reaction and excuses is chilling. There's no remorse, no embarrassment, no sympathy. He got what he wanted which was to make you feel scared and inferior and to make himself feel superior. Not the sex; rape is about an inadequate loser making themselves feel better through hurting another. I feel so sorry for you, you must be in pieces, but now is the time to act, not freeze.