Yes, two best friends can marry each other.
The provided reference highlights the potential benefits of marrying someone you know well: "Love, trust, mutual respect and effective communication are the foundations of a happy marriage. If you are marrying someone you don't know that well, it will take some time to work on them." This suggests that starting a marriage with someone you already have a strong bond with, like a best friend, can be advantageous. The existence of love, trust, mutual respect, and effective communication, traits often found in best friend relationships, creates a strong foundation for marriage. Therefore, there is no reason best friends cannot marry each other and create a happy marriage.
