I've not known anyone or anything that has as much potential of ruining a marriage as the ex. Almost all women will agree that they have a passionate dislike for their husband's ex even if she is an angel. Nothing can ignite the competitive adrenaline and testosterone in men like the wife's ex. It's crazy, yet instructive.
God has given us emotions that help us relate with each other and at the same time help us understand the kind of relationship we have with him. In many instances in the old testament, God likened the worship of foreign gods to adultery. He defines himself as a jealous God. In the new testament comparing the law with grace, he says you can't mix the old with the new.
Allow me to use this allegory. I have found it a strange practice that is so common in the church today that in prayer, people seem to be conversing with God and the devil at the same time. I think the devil is like that ex that we found was wrong for us. He's that psychotic ex who tried to ruin us and we have carried baggage into our relationship with God. We have trust issues because of him, and if we're not deliberate and careful, we will ruin our current relationship because of him.
So imagine that you go on a date with your spouse. In your conversation, your speech is riddled with statements like, "Ex, I am no longer with you. You have no power over me. My heart is now sold out for my spouse. I command you to release my joy..." I believe the only one who's trying to get convinced here is you. If any of this were true, you would be captured by the presence of your spouse. You wouldn't care who's out there. You would be absorbed in the conversation you're having, not distracted by the ex.
Many believers today find "power" in cursing the devil. There's a time and place for that, but note that that's not prayer. Prayer is what you have with God. There's no room for the devil in that quality time. It's special. If you want to remove darkness, turn on the light. If you want your relationship with God to grow, focus on God. Whatever you focus on grows. If you focus on the devil and the demonic, that's all that will grow in your life.
So it follows that if you want your relationship with your spouse to grow, you need to forget about the past and build anew. Remember, the devil made off with only a third of the angels. He is outnumbered in numbers, in quality of character and in strength. So keep it in mind that though in time past he had you cornered, Jesus in his might came and loosed you from the devil's hold once and for all. Now keep your eyes on him, Jesus, the author and perfector of our faith.
Have a blessed week.