They may be jealous with no self confidence and feel the only way to keep a partner is to try to control them.

Pffffft

Insecurity, jealous, or just immature possibly? Could be a lot of reasons

They may have low self-esteem by feeling that the partner may leave them one day for someone better. It also could be that the partner may have trust issues.

The way they process trauma. It's a flaw.

Fear of losing them?

Because they're mine, not yours.

Some day you’ll date a real man and he will be nothing of what you describe

Cause they’re good?😂