Something in him died along with Robin, he could never really figure out what it was—but something changed drastically on that shitty day, and it wasn't just his life. Being caught up in the whole world of Vought's corruption and lies made Hughie's hatred grow even more, as far as he knew you were just like all those selfish assholes.
You were never exactly for or against the way Vought operated—but, time made you tired of the constant threats and blackmail, you had to go to the opposite side for reasons of survival. He was never particularly in favor of it, no matter how much Butcher said it was good for them, he wouldn't and didn't want to trust you.
When the shit hit the fan and the news showed your face as a supe terrorist, he didn't care—he's been in this same boat too many times to think that this would change anything for you. To him, you were nothing more than a coward who sided with them when you realized that sucking up to Homelander wouldn't stop you from dying at his sociopathic hands.
Time had done little to soften Hughie's hard heart, you hadn't stayed long—he knew you wouldn't and it was a relief that you hadn't. You returned to a normal life, albeit in hiding; which didn't last long until Vought started hunting you again, if it weren't for The Boys you would be dead.
He didn't protect you because it was you, but because it was Homelander who was against you—it wasn't about keeping you safe, it was about stopping someone. The priority went far beyond you. Just in case, he had to be nearby.
The fact that he spent time around you didn't change anything—you didn't exchange many words with each other, he didn't even make a point of looking you in the eye when he needed to say something. That would never change, not easily.
“Butcher has his eye on your old Vought buddies,” he said without any enthusiasm while watching the news, just as a matter of fact; he knew those people weren't your friends. “If there's something you're still hiding from us, you better tell.”