Why is he distant now after a long time of chasing?

There is this guy I met in march and we clicked really quick. He used to be so communicative, so romantic, so funny and so caring. We have been talking since then and I was struggling with some problems back then, he has stood beside me despite my attempts of pushing him away because I didn't want him to get tired with my problems. He stayed regardless and over time I fell for him. And when I finally overcame the problems I was ready for him. But this time, over time he got distant. No calls, late texts, less communication, no romance, nothing. I talked him about it but he said there was nothing wrong and said he would be more careful but nothing has changed so I got frustrated and tried to leave but he didn't let me leave, he kept saying how much he wants me to stay, how much he loves me etc so I believed him but no, since that last time I tried to leave, nothing has changed a tiny bit. And each day we get further, I'm doing my best by trying to be understanding thinking maybe he just has lots of stress but I can't help but overthinking. What can be the reason?
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12 h
Thanks for opinions. I broke up with him and I feel lighter
Why is he distant now after a long time of chasing?
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