How long is o.k. to date someone before meeting his family?

I've been dating this guy for almost 3 years with an off spell of about 6 months because of this matter. I'm a very family oriented person and we both have 2 children and grandchildren, but this matter has been a problem after we hit the 1 year mark with me and he sees it as not important with our relationship. As it's surpose to be about us not the family in his eyes. He has met all my family as I want him to share everything with me and all events I go to. But he still goes to those places alone when it comes to his side. He goes to ex's house for all events where his children go. He does it for comfort for his kids who are 32 and 40 years old. We do not live together. Our families all live in the same area so I'm totally confused about what's right and wrong and only know what I feel and need in my heart.