I think his career is his love and that he has fear of commitment, maybe your girlfriend he really did love and he can't get over she married someone else.
Perhaps you even remind him of those days, I hope not, as to the reason he sees you.
But, if he has said you are "friends" and he has "no intention of every marrying" take those words as gospel because they came from his moutn.
He may be a "nice" guy you know? Hey, so sorry, please forgive me, I don't treat people wrongly and didn't meant to forget".
He can not expect you to sit back, take his call, once in a blue moon because he is too busy, expect you to sit back and not marry anyone, because he will never marry you, expect you to sit back, because he works a lot and has no time.
It's nice to feel wanted and to feel something, often called love, yet love is two people that just want to be together and can't wait to do so, be it in person, phone or anytime. You surely don't wish to live like this forever?
He may also be very lonely and like everyone has needs. That conversation you provide to him, as he is alone. He needs.
This is a friendship with some benefits .
Keep it that way and find your love of your live.
You can not read peoples minds unless you are a witch like me
What they say is the truth.
Playing a game as in " i'm moving on" to seek a reaction is childish.
If you wish to you can be honest. I actually have feelings for you, how about we give this a proper go.
See what response you get.
If still "Friend?" move on. Keep a friendship only.