One person is not co-dependent. It is the dynamic between two people, the relationship.
Which means that there will be issues that you carry, as well.

That is what you need to focus on.
There are many good books out on the subject - a good place to start is "Co-Dependent No More." I have some other titles I can look for that have been recommended to me....

Do NOT call him. Do NOT discuss this with him. I know that it is what you have always done, come to depend on (do you see the wording I just used?). You have to do something different right now, even if it feels wrong and unnatural.
You are going to have to take care of yourself right now, and going forward.

Don't focus on his feelings, his resentment, his journey or reactions. If he did read it, it is part of his journey and not something for you to be concerned about. You can't climb into his head, no matter how much you want to, or how convinced you are that you had that ability in the past (you didn't).

What kind of person do you want to be FOR YOURSELF?
What will you need to do to address your own co-dependence, if that is an issue? I can tell you that denial is a powerful, often-used coping mechanism. In my case, it kept me alive and able to grow and function as a child, but wasn't effective or helpful as an adult.

You have to concentrate now on how to live a good life, develop your own skills and strengths. It is not about saving the marriage, but saving yourself. In the process, the marriage might survive, as well. THAT CAN NOT BE YOUR ULTIMATE GOAL. You have to make this change of heart internally.
I know you said you come here to vent, you don't say those things to your H in your conversations.
Believe me, you don't have to say it out loud - your mannerisms, the times you "slip," the tension in the air, the way you hold yourself, your energy - all of it is being picked up by your H, even if only subconsciously.
You have to change the focus within yourself. Know, deep in your heart and soul, that you will be ok, no matter what happens.

Your husband is not responsible for you or your happiness. And if that sentence doesn't sit well with you, there is a good indication that you have some codependence going on.