Can a couple who has a strong, committed attraction to one another live together and not explore sex? I don’t think so, we’re only human.
There are plenty of books in the Bible that cite sex outside of marriage as a sin. I can imagine it would be really, really hard to live with Sarah before marriage and not have massive temptation. The simple way to honor this idea is to not live together until marriage.
(Acts 15:20; 1 Corinthians 5:1; 6:13, 18; 10:8; 2 Corinthians 12:21; Galatians 5:19; Ephesians 5:3; Colossians 3:5; 1 Thessalonians 4:3; Jude 7)
While we were dating, even the idea of staying overnight at the other person’s apartment felt like a hot topic. We didn't do that until after 9 months of seeing each other (6 months long distance), and even then we stayed in separate rooms, separate beds and (thankfully) had good friends double-check us on all of this.
“But Matt, we’re paying two rents. We can save $XXX/month.” Nobody said this would be easy, just that it would be right. Heck, I hope you guys get guy roommates and have a blast. I hope you gals get gal roommates and enjoy your time together. Bonus: Those roommates will keep you both on the right track.
It needs to be noted: Neither Sarah nor I have not lived a perfect life with flawless decision making. We have pasts just like everyone. However, once we grasped what God intended on sexual immorality and marriage, many decisions became simple. To know what we know and CHOOSE to go against it would be worse than ignorance.
Jesus loves you and wants to be in a relationship with you. There is nothing nearly as powerful as that love. To dishonor it is to willingly disrespect God.