Will he commit?? Why does he say I make him nervous?

I met my current partner through a blind date at a friends dinner party. It was kind of organised and he had just finished a relationship and I was single. We immediatley hit it off, exchanged numbers and the relationship grew very quickly. After two months he took me away and told me he loved me. I felt the same so over the next few months I spent long weekends at his house and he always said we will sort this all out soon (ie move in). It was bliss until a few months later he became quiet distant. He finished the relationship by saying he needed to be on his own but loved me so much and had never loved anyone like he had loved me. I was totally devestated as I really thought this was the man I would settle down with.After a few weeks we met up and went for a meal, then as the weeks passed we met up once a week for dinner and then also for Sunday lunch. It took 5 months before I stayed over at his house again. So here I am now, 9 months later. We have been away on some great weekends/holidays and I see him on a Thursday and a Sunday. We talk twice day on the phone. We have recently returned from a great week away for New Year. He said that I make him nervous???? What can this mean?He hates making plans and was very hurt from a divorce twelve years ago-I really am in love with this guy but am at the end of my tether as I dont know what his playing at-He is twelve years older than me and says that the age gap worries him-what will i do when he is 70! He feels inswecure about this and no matter how I try to convince him that I love him no matter what i dont think he believes me-HELP