Make an assumption that someone voted for Trump solely because of his perceived stance on gay issues and express a belief that Trump will betray the LGBTQ+ community if given the chance.
Heck, she probably voted for Trump for that very reason.
Trump doesn't care one way or another about gay issues, but he knows the religious conservatives who voted for him want something in return.
Trump will throw gay people under the bus at the earliest opportunity -- for example, if Kennedy or Ginsburg dies.