When it comes to marriage why brides cry especially in some Asian countries?

Cos in Asian countries...mainly India...its rich in culture , customs and traditions... Most brides...90% , live with their folks till the day they married.... its like leaving your family for ever and walking into a new one... its the fright of the unknown, risk ... uncertainness ...knowing ur moving from the place u trust the most !
And this part is built into the psyche of the bride as well as her mother...and her family :)
Hope this sum's up most of it !