I treat my relationship with the Lord like He is my closest friend who I can tell everything to...I'm candid with him, while also remaining respectful. Working on a relationship with Him in a very real, close, and serious way should dispel feelings of fakeness.
I haven't felt a feeling of fakeness in prayers in ages. And I'm so thankful for that. I hope any who struggle with this can get to that point too. It makes living life a lot different and a lot better, even in the harshest times.