Hello
From experience - and out of respect to both of you, if one partner states clearly that they are not ready for a relationship, it's not your job to persuade them otherwise - and you run a very real risk of getting hurt.
I would suggest that it doesn't matter why he doesn't want a relationship - what matters is that you have fundamentally different requirements.
If a man (or a woman) warns that they may hurt you, it's a very good reason to run the other way, even if (and perhaps especially if) his or her presence is making you feel wonderful at the moment.
Have you been honest with him and said you want a relationship? It's clearly making you feel uncomfortable at the moment and rightly so - this guy knows how he's been in previous relationships and is trying to protect you. I would listen to him and do what it takes to respect yourself and your own needs.
It's very easy to get swept up in the romance and wonder of early love but I would take extreme care....
Ask me how I know!