What makes Capricorns lose interest?

i was dating one, and he blamed work stress for being the reason why he had bad communication, but he cut off all communication. He hasn’t reached out in a month, and he avoids my instagram stories. He used to look at them all before. Last time i seen him, i looked great, we didn’t argue, had a great weekend, and had a passionate time together. it literally makes 0 sense how he could move on so fast and be so disinterested in me. Last time we talked on the phone, was a month ago, and it felt like i was pulling teeth to even get him to call me.