Using attraction as an argument isn't the best approach I feel. Pedophiles say that they are attracted to children for example.
Marriage has been between a man and a woman for thousands of years up to now. I have no problem with who people choose to love as long as they are consenting adults. Changing marriage like we have has opened Pajdora's box. Anything goes now. Who are we to discriminate against who someone is attracted to? In the decades ahead we will see new types of marriage allowed that would shock us right now. I would make that bet with a certainty. I feel that it should have been kept as a civil union. Now the cow is out of the barn as they say.