I'm going to ask a customer to leave
I'm concerned. Was the customer being disruptive?
To begin with, I've noticed that he is acting weird.
I'm sorry you are in this situation. It is expected that you are respectful toward customers. You shouldn't assume things just because they are acting a certain way.
He seemed like a good guy, a bit weird but okay. I am wondering what I did wrong by only assuming things about his personal life.
I do not think you should assume about a customer's personal life as it is not something you should be concerned about. You are only concerned about how to make this custumer feel more welcomed and enjoy their stay in your establishment and unless they are being disruptive and rude, there's no reason for you to ask them to leave.