The best relationships are those where the husband and wife are each other’s best friend. If you find it hard to open up your feelings to your boyfriend now, your relationship might be heading for disaster in the long run. You want to be able to pour your heart out to your future partner.
Or maybe it’s just talking about marriage that you find difficult? Many women find this difficult because they’re afraid to “lose face”. Or they’re afraid if they push too hard, the man will run. You’ve gone out with him for 5 years, I don’t think you want to go out with him for another 5 years with no commitment set in place. Start out with some open-ended questions like “Where do you see our relationship going?” At the end of the day, you have to share with him how you feel. And if he’s not responsive, you really might want to re-evaluate your relationship with him.