Take up boxing, talk to your girlfriends, have a big cry, but don't let your H know that you hurting unless you want him to also feel bad. (Well you can be hurting and let him know, but only if it's a small problem he can solve, but didn't cause)
Here is a good way to think. To him or any other man you are a happy well adjusted person without a problem in the world. Someone so easy to get along with and so desirable who doesn't have big issues or big problems with their personality. It wouldn't bother you if he went off with OW because your life would be better without him.
And don't listen to that advice about getting things out in the open or they cause built up resentment. Might be true, might not, but it's not relevent in this case. You'll resent this the rest of your life whether you talk about it or not.
The other night I wanted to tell H i was hurting and sad. Instead I said thanks for picking us up. You must've had to go out of your way to do that.
You are independant, you don't need his comfort or help, but if he wants to give it to you one day then you'll appreaciate it. It helps me alot for me to pretend I am an independant single mum and that H is just a boarder and has no obligation what so ever to do anything.
