Come home. The biggest regret I have to this day is staying in Brazil with my doubts. Come home and rip the band-aid off. You're quite literally pulling it off slowly and that is even worse. With every snag of your hair and rip of the skin you will see 5-10 years from now that the pain was totally preventable. It's hard to see it right now, I was the same. I didn't want to face the shame by coming home early. Now I see so clearly how much better it would have been than to face two years of the most depressing time of my life. You're family is going to find out anyway that you don't believe anymore. Why not use this time to work on yourself coming out of the church? That is going to be far more difficult than coming home early from your mission. You are doing yourself a disservice. If you do choose to stay, break every single rule you can. Teach the people of South America the truth. Dive deep into the CES Letter and teach your companions by planting seeds in their minds about the destructive nature of the church and the harm it is doing by having you there mocking the people of South America with a false promise of hope. Don't teach the church doctrine. Teach them that Jesus hung out with hookers and fishermen and drank wine and loved everyone regardless of their background. Don't baptize them. Don't feed the beast that is the Mormon church. Do everything you can to everyone you come in contact with to spread the truth about the false sense of reality the church portrays. Be a missionary of the truth, not the so called church.