Genuine question for the older guys.

Hey all, 19 M here and was talking for a bit with a guy much older (56). Really nice, wise and handsome man that does not look his age. We would text/ call nonstop until we met in person for a few weeks. After more talking and meeting up in person, everything felt right and he would tell me that every chance he got. This was around 2 weeks ago. We made plans to meet up again, but I slowly began noticing less frequent texts from him. Until yesterday, we were supposed to meet up and no response at all. He never stated any negative things, just flat out stopped responding. So my question is, what has made you lose interest all of a sudden during past times (if ever). Genuinely thought everything was going well due to all the sweet talk he would give. It just sucks because meeting older guys and building a connection for me is like everything I’ve ever wanted, but it seems it’s like as soon as they get what they want then it’s quits for the older guys I’ve talked to. Honestly no big deal. I’ve had this happened before and I learned. I just can’t help but kinda miss him?