Traditions are constantly being modified. "Under God" was added to the Pledge of Allegiance in 1951. Should we yank it back out? Anti-Miscegenation laws were struck down in 1967 opening up interracial marriage. Should we go back to allowing marriage only to couples of the same race? Traditions and the concept of marriage are not static. Your contention that they are is in error.
You're equating relatively minor modifications to marriage law to monumental changes in the overall concept of what marriage is. I'm getting the very distinct impression that you just don't understand how significantly radical what you're asking for is in the eyes and hearts of many people.
Sometimes the best way to respect a tradition by expanding it to be more inclusive.
And sometimes the best way to respect tradition is to leave it alone.
You have yet to establish a need for two separate sets of legislation. (A real need as opposed to just wanting it that way.)
And you have yet to establish a need to for the union of gays to be called marriage of civil unions provide the exact same rights and benefits.
Why is there a negative attitude toward gays? And who has this attitude? You?
I don't, actually. I don't understand the preferences of gays but I have no ill-will towards them nor do I care what they do in their bedrooms and I wouldn't hold that against them in my dealings with them. A decade and a half ago I had friends that were gay and it didn't bother me in the least. However, I
am offended by an insistence that I be forced to bend society's traditional definition of something as basic as marriage to accommodate their preferences. I'm willing to give you the legal rights. But if you push me to call it "marriage," no.