And I don't know how I can be so "in love" with him. I
But I wonder why he talked to me like that, and my co-workers didn't have a convo with this guy.
you've got a crush on him - it's really not the same as loving someone or being in love. you have to know people to fall in love with them. you have to know them very well to love them.
it can be very intense but a crush is a crush.
he may have talked to you because you seemed like a friendly, non-threatening person. he may be lonely without his girlfriend and child and was hoping to find some friends locally. with your crush, you're not a great candidate for that.
chat politely with him when you see him. don't avoid him. behave as normally as you can. he still needs local, friendly, faces.
Better luck on the next crush turning into something else.