A church family will help you from backsliding.
None of us are immune to temptation. Given the right situation, you and I are capable of any sin. God knows this, so he has assigned us individuals the responsibility of keeping each other on track. The Bible says, "Encourage one another daily ... so that none of you may be hardened by sin's deceitfulness." Mind your own business is not a Christian phrase. We are called and commanded to be involved in each other's lives.
If you know someone who is wavering spiritually right now, it is your responsibility to go after them and bring them back into the fellowship. James tells us, "If you know people who have wandered off from God's truth, don't write them off. Go after them. Get them back." - insert from The Purpose Driven Life, page 135.
This responsibility is our job and duty as believers and as the Body of Christ. So, keep in mind, We are our brother's keepers!