He went on vacation and stopped contacting me. Before that he texted me all day... Should I assume he's not that into me?

And that's the problem with the internet! This is a case study all its own about what the internet does to people. You were\ are in a fake situation, but it's causing real feelings. Unless you met him in person and spent even a little time with him, you can assume everything online is a facade.
People only show you what they want you to see, on the internet. That's why you cannot make a real connection. But it damn sure feels real, doesn't it?
Just let it go. I know, easier said than done, but move on. Don't let a facade cripple you in the real world. The feelings are real, they will take a few days to get over, but you will get over it faster than you think and you know in your head it's not real, it's just a matter of getting your heart to follow along.
After that, get more cynical about the internet. You can meet and greet online, but don't put much effort in unless you can materialize it in the real world. You don't know people. You especially cannot know them if they can control access to themselves.
Cut the cord, mourn for a couple of days and move on and be happy.
So he ghosted you? I say forget about him and move on.
Exactly, it only takes a few minutes to text you. He's basically stalking you now.
Opinion
1Opinion
He is laying pipe somwhere else.
Superb Opinion