Hi, I'd like to help you with your question.
It sounds like you are very aware of what you are feeling. You stated that you feel better and more self confident when you are not around your husband and you feel worse when you are with him. This can be one of two things.
First, you are feeling upset about what he has done in your relationship. It is natural and expected that you would feel a variety of emotions from anger to depression. When he is with you, these feelings come up and you start to feel less focused, less confident and upset. The separation has you left in limbo and you have no way to address what you feel about him and what he did.
Two, you have moved on from the relationship and have no desire to be with him anymore. So when he is around, you not only experience reminders of what he has done, you feel strongly enough about not wanting to be with him that you experience several disconcerting feelings in his presence.
Whichever you feel is more accurate is most likely the answer you are seeking. It would help you to continue your counseling if you are still going. If you feel it is not helping you, seek out a new counselor. Oftentimes, finding a counselor you feel you can work with takes a few tries, much like it does with your regular doctor.
Is your husband sorry for what he did? This can also be part of what you are feeling. If he has not tried to make amends and worked on the relationship, then you are going to be stuck feeling the same as you did when you separated. It makes it hard to forgive and work on your emotions if he is still treating you the same way.
Also, keep in mind that mourning your loss of a marriage and stable relationship is important, even if you decide to keep trying to reconcile with your husband. No one marries expecting to be treated badly and cheated on. You most likely married with the best of intentions and expectations. But you suffered a great loss instead. Give yourself time to mourn. Be aware of the stages of loss and let yourself go through them naturally.
Here are some books that may help you:
How To Save A Marriage: 92 Tips On How To Solve Your Marriage Problems Without Needing Marriage Counseling by Gary Vurnum
Should I Stay Or Go? : How Controlled Separation (CS) Can Save Your Marriage by Lee Raffel
Too Good to Leave, Too Bad to Stay: A Step-by-Step Guide to Help You Decide Whether to Stay In or Get Out of Your Relationship by Mira Kirshenbaum
Contemplating Divorce: A Step-by-Step Guide to Deciding Whether to Stay or Go by Susan Pease Gadoua
I hope this has helped you,