This might be hard for you to hear OP, but your husband is an abuser. A cheat and an abuser. You do not deserve this treatment in your life.
Pestering you for sex a week after giving birth and you feeling like you had to give it him to keep the peace - is sexual abuse.
A loving, caring spouse should never coerce, pester, guilt trip or force their other half to do anything they don’t want to do. No excuses.
www.mycwa.org.uk/sexual-abuse - if you feel up to it, please give this link a read. There are contact details if you want to speak to someone.
I really wish I had a trusted colleague or friend to speak to about this, but I know I just can't.
Is there a reason you can’t? Fear, shame, embarrassment? If so, please know, you have absolutely nothing to be scared, shamed or embarrassed about. Nothing at all OP! I promise there will be someone out there who will be willing to listen. Who will be willing to help you.
If you physically have nobody you can confide in, please contact Womensaid.
www.womensaid.org.uk
and I felt overall that the kids didn't deserve to pay for this. And neither do you, OP. You cannot stay with an abusive man for the sake of your children. If he is this unpleasant with you, surely your children will pick up on his behaviour and know deep down that it is not right.
It seems like you have had years of this. So I completely understand how terrifying it must feel to have a life outside of this marriage and away from this man. But you need to divorce. You can not stay with this man.