All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
"For them to remain as friends": If by this you mean that she sets a conditions before the marriage contract that he does not have sexual intercourse with her, then this is a void condition, and it is not an obligation to fulfill it. Please refer to Fatwa 193539. But if you mean that they agree to delay the consummation of the marriage, then this is acceptable.
If that man is religious and has a good moral character, then we advise her to hasten to marry him in order to protect herself from temptation. The Prophet, sallallaahu ‘alayhi wa sallam, said in an authentic Hadeeth: "If a man whose religion and moral conduct are pleasing to you proposes to you, then marry to him.”
A husband who is religious and has good moral conduct is more likely to protect his wife and fulfill her rights, and this will lead her to love him, because love can be found after having not existed. Besides, love is not a condition in making a home. ‘Umar said: "It is not only on love that homes are built." This means that there are many other benefits that can be achieved from marriage, like having children, and the care and safety that the wife enjoys while she is under the protection of her husband.
Allaah Knows best.