Too many men confuse love with ownership. Too often when a man tells a woman he loves her and wants to marry her, he means he claims ownership rights over her. In his eyes, this will give him the right to have intercourse with her whenever he wants, whether she wants it or not, the right to hit her and punish her when she does anything he doesn't like, the right to make her work for him - cook, clean, launder etc without his doing anything for her in return. Too often men think like this from near the beginning of an acquaintance - and any rejection is a hideous humiliation for the man, for which he has to get revenge in the most spectacular and horrible way, so the whole world can see what happens to women who reject men like him.
This is the way stalking happens - far more prevalent among men than among women. A man can't accept that a woman he wants doesn't want him. A man like this may have been intensely spoiled in childhood by both parents, giving him a "little emperor" complex - he develops delusions of grandeur and may develop morbid jealousy,a pathological/mental condition which cannot be treated and too often ends in murder