institution of marriage

we live in a world where after birth and education marriage is the most important part of a human being but some time i wonder that is it right to tie a person with other for rest of the life in the name of some social norms????
why two people can not live together without marriage???
wht is role of love in a obvious relation with wife and how one can "create" and "maintain" teh feeling of love for the whole life???
or the two can live together peacefully without feeling of love ???? just to complete a life cycle and shoulder each others responsibility with the feeling of respect........
and as long as marriage is a social institution we can not expect very nice personal result out of it
no body talk about love in the time choosing a girl or a boy but there are some fixed parameter
for a good husband and wife like one should be good looking with handsome earning with good family background and these social parameters are so deep that in the case love... girls prefer to love a boy with the same quality if they want to marry him.....
in 90% of the love marriages people use same kind of social parameter but the point of satisfaction is that they have chosen their partner... so what is the significance of "love" in the relationship called marriage????
in my point of view marriage is association of two people for competing a life cycle in a order where you reproduce and look after your off springs nurture them give them opportunity to grow and look after your partner with the sense of respectability and in the process if love happens it is a extra bonus because if love happens before marriage then it will become burden to continue and maintain but if it happens some where in between a relationship
it will the bliss...........