The states have never amended the Constitution to expressly protect so-called gay rights. So Congress has no 14th Amendment authority to make laws to protect such “rights.”
Unfortunately, that is not the way the country is being run.
Back in 1982 when Congress voted to cut off GI Bill Education benefits for flight training, I called my senator's office.
ME: "Why did you do this?"
Senator's office: "Oh, Congress believes that some people are just using the flight training for joy-riding."
Me: "So, how many guys go to college on their GI Bill to drink beer, chase girls & party?"
"How can you do this? This is a contract I signed in 1967. I go fight your war, you pay for my education, INCLUDING flight training. I have fulfilled my half of the contract. How can Congress now renege on your half?"
Senator's office: "Well, we know it's a bum deal, but basically, CONGRESS CAN DO ANYTHING IT WANTS TO!"