You're right. As humans, we always have the freedom to choose. It does sound like you have the right attitude about the power of prayer.
Here's another thing I used to repeat to myself -- The enemy is not welcome in my home. He can not occupy the same space as God, and God lives here! Dear Lord, please place a wall of your love around my home.
I swear to you that I could see a spiritual battle within my X (still do for that matter). Right before my eyes! It was amazing.
I only know what worked for me -- just some ideas.
Me 47 Ex H 46 Bomb 9/02 D final 3/04 Ex H now married to OW
------------ This is surviving. There is no such thing as a normal life, there's just life. So get on with it and enjoy it!