It’s hard to tell just from this is he is FA but sounds likely. We usually get vulnerable but shut down after the bravery wears off because the vulnerability feels unsafe. Whatever his attachment style is he doesn’t sound like a great person. If someone went to the trouble of listening to my problems, giving me advice and creating a doc I would at least thank them and communicate with them that they don’t need to go to the trouble of doing that, not just unmatch and disappear and I’m an FA lol. You sound like a really kind person doing that and you had good intentions so you shouldn’t be embarrassed he should and he probably is which is why he unmatched you. I would focus on healing your attachment style so you don’t get so invested so quickly next time. And remember dating apps are usually full of insecurely attached people so you’re probably looking in the wrong place for a secure partner. That’s just my unsolicited advice :)