@maura2424,
The ring is a gift. Unless it is some sort of family heirloom, he has no right to ask for it back, as he is the one to break the engagement.
As for the rest of it, I am so sorry. Can you see if you can go through an intermediary, one of his parents, a sibling if he has one, the pastor at your church? The man may want no more contact but you do need some answers, at minimum.
Hang in there. People do drift apart, and engagements have been broken before. You can recover from this, and you will. You're gonna be okay.