Awww poor you Despondent, you must be and you sound absolutely devastated. The one person that you're even closer to than your parents is your spouse and as Jesus said, ‘For this reason a man shall leave his father and mother and be joined to his wife, and the two shall become one flesh’ ? Matthew 19:5 NKJV So when that partner cheats, the effect on the unsuspecting party is going to be like a bullet wound.
You describe the hurt and attempts at forgiving as a battle. Can I please ask a totally inappropriate and insensitive question? Reflect on the last couple of years, and ask yourself, did I take my marriage for granted and could I have done better for my husband? If you can honestly say no I didn't and no I couldn't, then you had the misfortune of marrying a philanderer, and you're better off without him, and his bit on the side will soon find that out for herself. For you, move on and refocus your life on that other love of your life, Jesus.
If however your honest answer is maybe and maybe, I would ask that you give some consideration to the feasibility of reconciliation. Forgiveness would be a massive hurdle. Don't get me wrong, I'm not condoning infidelity, its wrong wrong wrong but if you can understand that maybe he was only 90% to blame, that could be a start. This is something you really really need to pray about, ask God what His will and plan is for you. If reconciliation really isn't feasible then move on and refocus your life on that other love of your life, Jesus.
I'd urge you not to wallow in righteous indignation but with the help of God, be strong and move on with or without your husband. Tell God how you feel and He may well remind you that even the best of us cheat on Him, the Old Testament is full of references to this. Ask for help in dealing with this because He's been there with each one of us. God can see and feel your hurt and because He loves you He wants to fix it and make it better for you. Forgiveness is important, be strong, be that first person to drop their stone and walk away; and then move on.
If you two do reconcile and I really hope that you do, and to anyone else married that's reading this I would urge you to work on your marriage every single day, especially in the bedroom - Do not deprive one another except with consent for a time, that you may give yourselves to fasting and prayer; and come together again so that Satan does not tempt you because of your lack of self-control. I Corinthians 7:5 NKJV. I'd go further, not just not denying but initiating. Tantalise your loved one, shower with him/her with love and affection, learn how to please - work on it.
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Dear Lord God, I really feel for poor Despondent, she's obviously wept buckets about how awfully her husband has treated her and just abandoned her. Please please please God, work in her with your Holy Spirit and give her the wisdom to ignore her heart and knee jerk and instead to earnestly seek your will in her life. We know from past bitter experience that ignoring you and doing what we want doesn't usually end well.
Through your Holy Spirit, make her an absolute tower of strength to take charge of this awful situation and bring about a healing firstly in Despondent's wellbeing and subject to your will, maybe in their marriage. This is a pivotal moment in her life, and I pray God that she follows your will and way.
Long term God, I pray for a special blessing for her, happiness for her and not self-fulfilment but rather you-fulfilment.
Amen.