1 Thess 4.3 For this is the will of God, your sanctification:£ that you abstain from sexual immorality; 4that each one of you know how to control his own body£ in holiness and honor, 5not in the passion of lust like the Gentiles who do not know God; 6that no one transgress and wrong his brother in this matter, because the Lord is an avenger in all these things, as we told you beforehand and solemnly warned you. 7For God has not called us for impurity, but in holiness. 8Therefore whoever disregards this, disregards not man but God, who gives his Holy Spirit to you.
Its DISHONORING yourself
1 Cor 6.13...The body is not meant for sexual immorality, but for the Lord, and the Lord for the body. 14 And God raised the Lord and will also raise us up by his power. 15 Do you not know that your bodies are members of Christ? Shall I then take the members of Christ and make them members of a prostitute? Never! 16 Or do you not know that he who is joined to a prostitute becomes one body with her? For, as it is written, “The two will become one flesh.” 17 But he who is joined to the Lord becomes one spirit with him. 18Flee from sexual immorality. Every other sin a person commits is outside the body, but the sexually immoral person sins against his own body. 19 Or do you not know that your body is a temple of the Holy Spirit within you, whom you have from God? You are not your own, 20 for you were bought with a price. So glorify God in your body.
Rev. 22.12“Behold, I am coming soon, bringing my recompense with me, to repay everyone for what he has done. 13I am the Alpha and the Omega, the first and the last, the beginning and the end.”
14Blessed are those who wash their robes,£ so that they may have the right to the tree of life and that they may enter the city by the gates. 15Outside are the dogs and sorcerers and the sexually immoral and murderers and idolaters, and everyone who loves and practices falsehood.
Eph 5.31–32 For this reason a man will leave his father and mother and be united to his wife, and the two will become one flesh. This is a profound mystery—but I am talking about Christ and the church.
So why would you want to be with someone who doesn't want to be with you enough to do it right? Why should YOU compromise with a coward? If they can't commit, you must omit (them from your life.) The harsh reality is that even though it hurts now it will hurt less than when the coward finds someone else more interesting later on.