Surprised at the sudden confession, Kyle didn't know how to react. He just sat there and let Gabriel go. Shit...what do I do now?

Yes. He knew that he acted like a fool. He should wait to let them get to know each other. Maybe then he would have a chance. But 'maybe' was too small. He knew that it would be getting worse for him and more more time would pass the more rejection would hurt.
Normally he would not mind deceiving anyone but he didn't want to do it to Kyle. He deserved something better than a friend who actually has only dirty thoughts about him.
Gabriel noticed some bench and sat down on it. He hid his face in his hands.
Why does everything have to be so difficult?

"Hey Gabe. What's the long face?" The voice didn't to Kyle, instead it belonged Trevor. The man you met before.

"Ugh. Hi, Trev. Just... life being difficult I guess..", he said tiredly.

"Yeah lifes a bitch like that and I'm suddenly free since the professor ended up throwing up everywhere. Not exactly what you wanted to see during massage therapy, not a turn on unless you are into that sick stuff," Trevor tired to get Gabriel to smile and looked around. "So..."

Gabriel laughed, unable to help himself.
"You're a funny guy."
He again became serious.
"But you'd better leave me alone. I just said something yo Kyle after which he will not want to know me so you have no reason to talk to me if it's not about him, right?"

"You know, talking like that is bad for you. What did you say to Kyle anyways? If you don't mind me asking of course," Trevor flashes his own smile with a goofy twist and waits to see what happens.

"I like guys so think one more time if you really want to know", Gabriel said grimly.

"That's it? Seriously, I thought you were gonna say you are a murderer or something," Trevor states as he gives Gabriel a hardy slap on the back. "Come on, let's go find Kyle."

"No. I can't do that... I... I like him. I can't just be his friend, ok? I just fuckin' can't.. ".
He again buried his face in his hands.