Seriously, why is dating (girls) so hard?

Anonymous
This is just gonna be me ranting because God knows how tired I am of how dating works.
I just wanna know if this is only happening to me, or if that's an actual thing for everyone:
I've been on dating apps for a while now, and most of the time it just doesn't work, which is normal in my opinion. But the thing is, every single time it does work, the *same* pattern happens again and again. Litterally every time, for the first 2 days or so, it goes really well, the conversation is nice, we have fun and the other person says they liked talking with me. Cool right?
Well yeah, except that every time, after those great 2 days, the person just gets more and more distant. Somehow, when everything's new, they find the time to talk to me sometimes for hours in a row. But suddenly they're "so busy" or "so tired" they end up messaging me later and later, less and less, until I'm fed up and don't bother carrying the conversation anymore.
I just wanna know if I'm doing something wrong? I know I'm not perfect, but I try to always be nice and respectful of others. I ask questions, joke around, don't mind serious talks if that's what they need atm, etc. Like really I do huge efforts because I want to treat people just the way I want to be treated myself. So why is this happening all the time? Does it happen with everyone? Am I doing something wrong?
I honestly have tried many things. I tried to play hard to get cause I don't know maybe people want me to be less available: it doesn't work. I tried to be flirty, funny, supportive, god knows what else: still not working. More than anything, I tried to be *myself* and sadly it clearly doesn't work either.
My self-confidence is dangerously dropping. I just find it heart breaking to see that I can't seem to find someone interested in me for more than 2 days, despite my best efforts...
Please can you guys tell me if I'm doing something wrong or if that's a common thing?

I'm really clueless at this point as per what to do.
Seriously, why is dating (girls) so hard?
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