Oh my gosh, I do feel so sad for you @SingleRoo123 you sound so confused, upset, and wounded. And it's hardly surprising! What an absolute piece of shit this man is. Why do men do this? WHY? 
I think if you asked every woman you met if something like this had ever happened to them, they would say yes. Sometimes several times! Men do chase for many weeks, sometimes many months, and then get you into bed, and then never get in touch again. As a previous poster said, it's the thrill of the chase for many of them, and once they've 'had' you, they move onto another woman.
I've been convinced a man was 'the one' 4 or 5 times (way back in the past before I met my husband,) as said man was all over me, complimenting me, showering me with gifts, calling me all the time, and buying me flowers. Then after 3-4 months, I gave in and shagged him, and it was like I didn't exist after that.
I was left perplexed, hurt, angry, wondering what I'd done wrong. I called them and left messages but never got a response back. Just cut off. Ghosted. Happened 5 times over several years. I actually stopped dating after the 5th time, (for 2 and a half years!) Then I met my now DH ... I made him wait a YEAR before I slept with him. Poor bastard. He was so patient. 😆
A few days after we first slept together, he rang me and suggested we start looking for a flat together. So I didn't get ghosted that time. (Still married over 30 years later!) You will find a man who deserves you OP! 
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