Why can't guys be straightforward with their intentions?

I started talking to this guy a bit more than a month ago. We found each other on the app so of course I was being a bit cautious with where things could go. I'm the type who's not into one night stands, where most of other guys are.Anyway I kept talking with this guy and he's really funny, we have kind of the same humour and I really liked how knowledge he was.We even met for a drink, even tho it took a while to get him to come, he almost never had time or was lazy. When we were on a drink I had a good time, even tho we were mostly joking around. I asked him about his relationships, his life, what he's doing, all that stuff.So New Years comes around, we don't talk much and we don't go out because he was busy again, so I say I won't bother him until after the holidays are over.And last week I write to him. We start talking again, like we did before and he's also super willing to go out again, which is a surprise because I was usually the one asking him out.I then jokingly say: "Wow I'm honoured now that I can go out for a drink with you again. You must have a lot of guys asking you." To which he replies: "Haha not anymore since I'm in a relationship.'Seriously it was like a punch to the stomach... All the effort I tried putting into getting to know him, gone like that.Now who am I to say who you should love. All I want is for people to be straightforward. Is that so hard? Almost everyone in the gay community is already sorting themselves by tribes and what not, thanks to the apps we have. But no one cares to even use the relationship status bar? Or just write down in your bio, tell me when I ask about it, etc..I know most of you are going to say you shouldn't attach to someone so soon or just keep an open mind. I don't know, maybe I started to kinda like him, maybe not. What I know is that I put in an effort to talk and get to know him and not once has he implied he's in a relationship, even when straight out asked so.I feel like shit because I always try to be nice and really get to know someone. Then same thing happens everytime. I once even had a guy who told me he's looking for anything that might come up, but after some months of talking he said he's married.How should I deal with this or find someone who isn't like this? Because I feel like a mess everytime it happens.To put salt on the wound, the guy I wrote the post about (Not the married one) also blocked me from Facebook and unfollowed me on Instagram, after I told him how I feel and hate that he wasn't being honest. :)