Why can’t you tell friends of the opposite sex that you miss them?
Say they’ve been AWOL. You miss hanging out. So why is it so difficult to pick the phone up and say ‘dude I missed you’ without implying that you want to bodyslam them against the nearest wall and suck on their face like a cola-flavoured Chupa Chup?

You don’t just come out and say it. Even though you mean it. It’s a loaded sentence. It’s a verbal bomb.
And you can’t clarify it. For instance, “Dude, I missed you! But only as a friend. A platonic, male friend. Whom I occasionally hang out with and have no romantic inclinations towards whatsoever.” You can’t say that.
You might as well paint DENIAL on your forehead. In chocolate.

The only other way to say it is as though you’re speaking on behalf of a collective: “Dude, we missed you.”
Not only does it come off as insincere (“Oh look, there’s What’s-his-face, stall him until someone remembers his name”), but it brings to mind the idea that an actual meeting was had to decide this.
Kind of like a mini funeral. Without a dead person. Which is creepy.
(Speaking of which: do midgets have mini funerals? I’m sorry, stars of Little People Big World, Frankie Muniz and other worthy midgets. But that’s an awful lot of coffin space going to waste right there. )
And you can’t even say that unless you’re sitting with at least one other person. Otherwise your backup will be a wall and a chair. “The chair missed you! Look, your butt print is still there from when you sat on it!”
The other, roundabout way to say it is to wait until a huge chunk of your friends disappears and you can say it, as a group, when they return. “I missed you guys!” Unfortunately, this is rare, and unless you personally facilitate this by pushing some of them off a cliff it’s not going to happen.
(That being said, who wants to go on a hike next Saturday?)
Other failed sentences include:
“I missed hanging out.” This means: I have no friends.
“I missed talking to you.” Wall, bodyslam, Chupa Chups, now. Also, let’s get married.
“I missed picking on you.” I have abusive issues.
There just isn’t a way to say it.
Well… I missed you, man.