Coulter is against homosexual marriage.
When she spoke to GOProud she convinced them that it was a bad idea, and they took it off of their agenda.
Supporting Romney is anathema to that position.
LOL, she hardly gave a full-throated invective against gay marriage, which she always does against everything she's really against. The implication in her remarks is to quiet down about it "for now." That makes it easier to sneak it through the courts like happened in Massachusetts under Governor Mitt Romney. The more people raise the gay marriage agenda, the more the public does everything they can to try to stop it, including influencing the courts, amending the constitution, etc.