Standing is a process with a beginning and an ending, and thus consider Stander a temporary label. The process and label continue until you choose to no longer Stand or want marriage to your spouse or former spouse, or until Standing is no longer a necessary process in the salvation of your marriage--until rebuilding and reconciliation. Give up the label when it is time, to cling to it is to prolong the process, not necessarily of the MLC, but of the marital-crisis and separation.
This is a recipe for codependence. Codependence is often referenced within the context of two people, and this may apply to you. But codependence is regarding your situation, regardless of whether there is an external recipient such as your spouse. A victim of a brutal crime may stifle recovery by identifying her Self with her pain and thus clinging to her healing process. Feel your pain, but also recognize that it is not you, but a step in the healing process.
Are you investing part of your Self-identity in your pain and survival? No one wants to Self-destruct, but if you are investing your identity with a situation and emotions which you would prefer to not experience, you are preventing your healing and thus the end of the experience--because to destroy your pain would destroy a part of your Self. To move on and away from the crisis, you must cease to identify your Self with the crisis. Congratulations, you are a survivor. But just as I asked earlier, who are you when your Life Story changes? Denial of the process of MLC prolongs it, but so too does identifying your Self with your role in the crisis.
Consider also how your spouse feels. If you are self-identifying in the context of betrayal where you are the betrayed--whether it is victim or survivor--you are continuing thus to identify your spouse as Betrayer. You are not allowing him to move on and are not acknowledging his growth and changes. Betrayer is what he was, not what he is.
I have no idea where to start. I need serious help.
You are going to start with working on your SELF. It's all you can do. You have likely become too dependent on your marriage--being a spouse and parent--for your Self identity. Who are you?
I believe anyone can do this, but not anyone will do this--Stand for their marriage. You can do this. You will get through it. You may fight parts of what you need to do. Sometimes you will slip--you also have a process which you are following. But before anything, start working on your Self.