HappilyEverAfter:
One of the first things that I would tell you to do is to grab the book
Surviving an Affair either here or from your local bookstore, and read it. Next, I would recommend that you might want to try coaching with one of the Harley's through their phone counseling service (888-639-1639 for appointments).
Your husband has been having many affairs for the last five years. Why is that? Has the marriage been incredibly unhappy for him over the last several years---and have you contributed to this poor state of marriage??? Or does he have a chronic sexual addiction problem???
If you feel that you've been a poor wife (that's no excuse for your husband's behaviors)---and by that, I mean that you have not protected him from lovebusters or met his important emotional needs (read the concepts here, and it's covered in the SAA book too)---AND you want to see if you can correct your behaviors and take a shot at restoring the marriage---then I would recommend that you consider a Plan A approach. This is where you spend some serious effort to eliminate lovebusters and meet your husband's needs, in an attempt to separate him from his "affair"---in this case, his thoughtless treatment of you.
In this particular Plan A, I would suggest you be very honest (without lovebusting) to your husband. Introduce him to the Policy of Joint Agreement---never do anything without an enthusiastic agreement between spouses. See if he's willing to follow that (HAH!). Let him know that his unwillingness to consider your feeling and lack of negotiation is killing your love for him. Give him a limited time (I originally thought about 30 seconds---but you should probably give it a couple months) to respond to YOUR changes.
At the end of this period (or right up front, if you've been doing a decent plan A already, or are worn out by this situation)---you should go to a no contact situation. That's Plan B. It should protect your feelings for your husband (because he won't be hurting you daily with this stuff), and it will also let him see how well you DO meet his needs. Plan B is begun by a letter stating that you are willing to work on the marriage, but not under the current circumstances---and you will hang on hoping that he will be willing to work with you to.
The fact that you have no children, he has had multiple affairs, that he has an OC from one of these, that he has not apologized, that he does not protect you from his thoughtless behavior (doing what he wants with OC regardless of your feelings), and that he does not protect you from the other family members---it would lead me to ask you what benefits do you see from this "marriage"? I hardly ever recommend divorce for anyone around here (and my wife had an OC herself that I am raising)---but I could certainly understand pitching the bum.
So, why do you stay in this situation? What benefits do you have in the marriage? How does your husband treat you otherwise? How "in love" with him are you?
We'll try to help...