You should also research the Islamic term "mahr", which they translate as "dowry" but which is more accurately understood as "bride price". To get a Muslim wife, the husband has to put up money up front. Officially, this money goes to the woman as her property in case she is divorced. In real life, the father tends to hold onto it for her
A woman who loses her virginity, or otherwise lowers her status, has destroyed her market value. With no market value, the obvious thing for her family to do is kill her