Your honesty and contrite spirit in sharing this is a good and hopeful sign, for God looks to the one who is meek and quiet and trembles at His word, and a contrite and humble heart He will not despise. You have named clearly what happened, that you entered a relationship you knew was outside of God's will because of loneliness, and that you have now ended it because you were unequally yoked. That decision to step away, though painful, was right and obedient. To cleanse ourselves from worldly things and to strike our roots deep in His instructions is how we are fortified, and you have taken that difficult step.
It is understandable that you feel torn now. You can know at the same time that it is for the best not to speak again and still feel grief and disbelief that the silence has come after so much shared history and a friendship before dating. Grief often lingers even when we know a loss is necessary, and healing does not happen all at once. Like a tree that receives many strokes before it bears fruit, the Lord often works through patient, repeated hearing of His word and steady trust. Do not be discouraged that the ache remains after a week. Give yourself time to grieve with lowliness and meekness and long suffering, being lowly not only in words but in your bearing toward all, whether friend or former friend, without quick anger or bitterness.
You were wise to tell him you would no longer reach out so as not to disturb him, especially as he faces health problems, and it is right to keep that boundary now. When someone has blocked contact and stopped responding, that boundary should be respected. You also mention looking back and seeing signs that he was emotionally and psychologically abusive. If that is so, then the distance is not only a matter of obedience but also of protection. It is for your good and for his that you do not pursue further contact. Do not insult him in your heart or with others, and do not seek to rekindle what was not built on the foundation of faith in Christ. To suffer a wrong patiently and to speak no ungenerous word is the way of freedom in Christ, and it keeps your own tongue and mind clean.
In your loneliness, turn now to the Lord rather than to another relationship that would pull you away from Him. Salvation is through Jesus Christ alone, and marriage as God has ordained it is a lifelong covenant of one man and one woman, with intimacy and living together belonging only within that covenant. Any relationship outside that pattern cannot be blessed, however strong the feelings of companionship may be. Ask the Lord to help you to be content in Him, to be rooted in His word, and to seek fellowship and counsel in the church so that loneliness does not again lead you into disobedience.
I will pray as you asked.
Father, in the name of Jesus Christ, I ask for Your mercy on this sister and on this man and his loved ones. Grant him salvation if he does not know You, and draw him to true repentance and faith in Christ alone. Bring healing for his body and mind and spirit according to Your will, and watch over those close to him. For Your daughter, grant comfort in her grief, strength to keep the good boundary she has set, and healing from any harm she experienced. Give her a renewed and contrite heart that trembles at Your word, cleanse her from worldly desires, and make her roots go deep in Christ. Teach her lowliness, meekness and patience, and fill her loneliness with Your presence and with godly community. Guard her from returning to what was not of You, and guide her steps in wisdom and purity for the days ahead. Amen.