ya it's easy to ridicule something like this. but truth is this could happen to anyone. he got emotionally invested pretty fast and definitely quicker than her and lost his mind. or lets say the rational censor. then he panicked and tried to fix it and the more he tried to fix it the worse it got. she wasnt completely off put in the beginning just a bit irritated. but he was so anxious about losing her that he couldnt hear that and kept going until she seriously felt uncomfortable.
point is he is no clinger or anything, he just got caught in the trap called (early) infatuation. and that clouded his judgment. and frankly what to do, or better lets say how to cope with that problem, i am not so sure of myself. you can always say spin more plates and next and there are other ones and she is not special, but if you feel it, you just do feel it.
and i think it is a more pronounced version of what we can read on this board pretty often, "he guys, met this girl/woman, date went well, we had sex/makeout/kissed, now she wont answer me and becomes distant and what should i do?" and so on. And i get the idea that often times exactly the same thing happened like it did here, somehow that insecurity got messaged through the convo, and she notices it and the guy kinda has his worries too, so he does stuff to make it better, but she is already on to him and so anything he does will make her even more suspicious until she reaches that point where she thinks, that is not what i want, it makes me uncomfortable, i feel pushed, whatever.
all i can come up with to solve this problem is, even if she seems the most precious thing ever, you cant be afraid of losing her. you welcome all that it gives you and value it but you have to let go at the same time. of course truly knowing that you deserve it might help too. because then you might be less worrying that it will be taken from you again. but theory is one thing, life another.