I'm afraid my response is only that I can empathize. The reasons for your difficulty are too complex for an easy answer to be known since we ARE dealing with people after all.
I've been on here more than 10 years. I've found it VERY difficult to connect with people here. I can't guess at what the biggest reasons are for that. Trying to figure that out feels like speculating into the wind. I don't think this medium makes people WANT to connect. It really encourages popping in and out like a whack-a-mole. A quick in and out before you get whacked with/by something/somebody 'weird'. For example, most of the time in chat (the only place where you directly interact with people real-time), IF I get the chance to PC with someone, it often feels like the other person's attention span is that of a 5 year old. In those instances, it's like they're watching a movie or YouTube video, or looking at some other website, or watching the neighbors out the window... doing anything besides paying attention to our chat. They can barely eek out short, pointless phrases that make me wonder why are they even here?! My sense of self isn't formed by what I encounter here, but by engaging in chat, didn't we kinda sorta a little bit agree that we wanted to, you know, chat? And usually before not too long... POOF!... they're gone without a word. I know people get booted off suddenly. It's happened to me. I'm not talking about that. Usually if that happens, the person will show back up in the main room with an "Oops, got booted". The poof-and-they're-gone thing has happened way too frequently that I know it's not that they got booted. They just left cuz whatever reason, they got bored, who knows why. If you're not going to make an effort, stop wasting my time! That's why I can go months between times I enter the chat room. It's almost always a huge waste of time if you're going there to try to connect, which I'll admit, I do. Not "Will you marry me" kind of connect, just hey, let's spend a little time sharing something about ourselves, and asking questions that engage the other person. While I have had some chats like that, and it's great when it happens, sadly they're so seldom that I rarely want to even try anymore.
Part of it is the amazingly transient pace of life these days as technology (the internet) allows instant gratification for information and interests. We suck it up so fast that we're onto the next thing before we've even stopped to look at where we just were. With such a pattern, no wonder connection on here is so hard. We feel odd enough as it is with this tickling thing (not all, but many I know do). We can't even find connection among like-minded folks. And I think that's what's so hard to grasp. In a place where, ahhh, finally I can find some people who might get me, nobody seems interested in even looking at each other, even acknowledging we're here.
As I think more about it, it's got to mostly be the sensual/sexual nature of tickling that makes people wary. People with non-sensual/non-sexual interests connect all the time... people into cycling, people into scrap-booking, people into hunting, people into cooking, people into oil painting. There's nothing sensual/sexual associated with these activities, thus no reason to have a preemptive guard up from the very start. Exactly the opposite actually... "Hey, this person likes cooking like I do. This should be exciting getting to know this person." Add the sensual/sexual thing in though, and the whole dynamic is something very different. We are asking a lot to expect someone not to have their guard up I think.
HOWEVER... there's no excuse for engaging someone in PC only to grunt a few words and LOL the whole time, and then poof away suddenly! Why were you even there to start with?!