Going on a vacation with your boyfriend may not seem to be a big deal, but trust me it is. I believe you are both seeking to please God and pursue sexual purity. The problem with traveling together alone is that you are giving the enemy an opportunity to tempt you. In 1 Timothy 5:13, the Bible exhorts us to give the adversary no occasion for slander.
You can not trust your flesh. As Paul would say nothing good exists in my flesh because he understood the horror of its works. That is why accountability is key in any relationship. Since you are alone, it is easy to be tempted to engage in things you would otherwise not do due to accountability. You end up becoming presumptuous and consequently fall into the snare of sexual sin.
But you may claim that you are mature enough to handle the situation. This boldness and false trust in self is what will destroy your soul. In 2 Corinthians 10:12, Paul taught that “let anyone who thinks that he stands take heed lest he falls.”
If you are an honorable vessel and you believe so, then set yourself apart as holy and useful for the Lord. Avoid anything that may stain that purity.
This is my advice to you, “you should flee youthful passions and pursue righteousness, faith, love, and peace, along with those who call on The Lord from a pure heart.” (2 Timothy 2:22).
Other inconveniences may occur, such as having to live in the same room yet you are not a couple. This exposes you to all unnecessary temptations which would have otherwise been avoided by not going on the vacation.