Hmm... this is just a suspicion. But one possible reason could be that you're too serious and not playful enough.
I could totally miss the mark here, but that is what I've seen in my own life. I make a friend am too serious, couple of months later I am all by myself again.
So I decided to become more playful, and that really worked! If you are noticing that you might be too serious yourself and might need some playfulness. Here are a couple of things I did:
1. Asking: how am I naturally already playful, I enhanced that. I simply looked harder for more situations to utilize that playfulness.
2. Understanding: what is playfulness? It took me 2.5 years to understand that it means to not be serious (e.g. the sky is purple and there BE CATS ON CATNIP ATTACKING US! 2.5 years of trying to get an emotional feel for playfulness. Yep, it didn't come easy but now I have a hang for it. It's quite fun :)
3. What type of playfulness can I do?
This list is non-exhaustive. Note: always err on the side of being respectful if you feel a that a certain form of playfulness is too difficult to pull off. If you don't do that, then you risk being a little mean, and a little offending and all those things. It's not the end of the world, but it's simply not nice.
The types that I know:
- The roleplay: I once approached a woman in a club pretending I was her long lost brother and that I was raised in the jungle by apes and that I was still learning her language speaking very broken English. She laughed her ass off and played along. Who knew that pretending to learn English could be so fun!
- The fantastical exageration: I already provided an example of that.
- Teasing: teasing is like trying to hurt the other person with the twist that it should be positive and not actually hurt them. If this idea seems confusing, err on the side of being positive and not hurting people.
- Trolling: it feels like teasing but it isn't. You basically try to fool someone a bit, but you do need to see if they are able to take it. Err on the side of caution and safety. One friend I have used to be a bit rigid. He's gotten used to me now. So with him I could be quite light saying like: "look, it's a red tree." "No Mettamage, it's brown!" "No it's red, it's like a hellspawn from Satan!" "What do you mean, it's so clearly brown, what are you smoking?" "Everrryything my friend. Want some? ;-)" "My god dude, everything? Haha, you're crazy mettamage" "I know :-)" "Hit me up" "For sure" "Oh, yea, now I see that tree is totally red!" (just to be super explicit: the smoking thing was a roleplay, no one smoked anything)
- Musical improv: I did this since I was 4, it's second nature. Just pretend that life is one big improvized jazz band and hum and dance along with it to whomever you're talking to. It's quite Disney-like really, like some Disney character suddenly starts singing.
4. What happens if I fail? Are there failure modes that I can't recover from?
If people simply think you said something silly but weird, you're fine. If you went a bit controversial and tried to be playful that might pose a problem, so the tricky bit is to stay light. My guide is to stay respectful, that helps a lot.
5. Are there forms of social imitation I could learn from?
- Watch comedy that you like but is popular
- Go to improv classes