Agreed with the other selfish comments but getting him to see that is more the challenge. He's being an *** and the only comprise is to have him see how much you work.. Being tapped out at the end of the day is one of the key things he could work on. I'm sure you'd be all over him if he showed and did things to reduce your stress, and at the end of the day you truely felt like you could give. Demanding things his way without giving you anything is just rude and unloving. It takes two to have a relationship and his effort is directed towards fullfilling his goals without addressing yours. That isn't fair and isn't a balanced relationship.
Granted he sounds like a jerk of a husband, you have allowed more than many wifes, web sex, would send many wives into a rage. Still once a week is not a lot of sex. Counseling is an easy answer, but not always an option, cost, time, unwilling partner. I think a compromise is need, I know this sounds crazy but you need sit down and talk about whats going on, sexual and behavior wise, Then negotiate "He really makes me hate him sometimes" have him work on his behavior. And you cater to his sexual needs some. *** for tat, explore his and your fantasies. role play. it is going to be difficult but it could be fun, for both of you. As far as him wanting some on the side, NO thats not going to make things better at home for you or the kids. He can get all he wants on the side after the divorce. Make sure you tell him. one thing you never mentioned the one time a week, does he please you or is it. wham bam thank you mam are you pleased does he even care?
I think he is being really selfish, but a marriage is a partnership and maybe removing (or reducing) the reasons he gives for his behavior will tell you if he is just a jerk or if he is genuinely unhappy overall.<br />
Either way, if you value your marriage, I suggest counseling. You both need a safe, ob<x>jective forum to speak openly and without getting into a fight.