It's just something you have to condition yourself with because you weren't exposed to it a lot when you were younger.

My boyfriend is the same way. You just have to ask him to take time/stop and when you're ready/feeling better about physical contact do it again. It also helps if you try to initiate things every once in a while, too, and ask him to let you control the level of contact. He sounds like a long-term keeper!

Just remember to keep lines of communication open with him. ;D