"12 See to it, brothers and sisters, that none of you has a sinful, unbelieving heart that turns away from the living God. 13 But encourage one another daily, as long as it is called “Today,” so that none of you may be hardened by sin’s deceitfulness." Hebrews 3:12-13
It's difficult to stay faithful, I think that's a fact. But it's not impossible. That's why support and encouragement from fellow believers are so important and vital in this spiritual warfare. When we surround ourselves with people who has no idea who God is or those who denounce the very existence of Him, it's easy to get sucked in and turn away from trying to live for Him. We need to encourage one another. We need to support one another.