What you should do is leave the man alone. Your instinct that he is “interested” may be correct. But he also knows himself well enough to know that his other issues and fears are bigger than his interest. He’s probably right about that. Give him room to figure himself out. If he does and is truly interested in you, he will get in touch. In the meantime, understand that a coffee together means only that you are spending a pleasant half hour having coffee with a friend. If you can’t do that, then do both of you a favor and decline the invitation.
You are in your 40s. I understand why it is difficult to give up on a man who interests you and who seems to be interested back. But this relationship isn’t going to go where you want it to go — at least not in the foreseeable future. Take a big step back and make the effort to find someone who is as available as you are for a deeper and more committed future.
I wish you well.