Thats why their are things called civil unions. As far as other things, like visitation rights, you can draw up a contract with a lawyer that would allow those rights that may not be specified under civil unions.
This is not about hate, this is about upholding the "sanctity" of marriage. Marriage always has been and always will be a religious affair (this does not need anymore explaining).
The problem is you cannot have equal rights when things are not equal. There are differences in either situation, and if things are different they cannot be treated equally.
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BTW:
mar·riage ( P ) Pronunciation Key (mrj)
n.
The legal union of a man and woman as husband and wife.
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