Marriage is all about promises, goals and boundations.
In truth you are confusing both and they are really not tightly related to each other and you must try to understand each of them. When marriage evolves out of Love and a mutual need to stay close to each other only then it can be something worthwhile. But both persons must be mature enough to understand the idea behind marriage.
Marriage is not important and should not be a condition to enjoy Love and be happy. I think the other person is being honest with you and saving you from many problems that are bound to arise in future.
When you say you don’t want to loose him — this very statement implies that he’s really not “close” to you and a part of you. A very deep understanding about Love and Life is needed here. The very act of stopping and controlling the relationship means deep inside you believe that you are you and other is not a part of you. You two are not one but seperate entities. And he can only give you Love when he’s separated from you. Exchange is really possible in two persons.
When there will be Love – people become not two but One. No exchange is possible, no control is possible, no domination is possible, no marriage is possible, no seperation is possible because you are really One and not two.
I think I must stop now and suggest you to relax and let it be. All problems will disappear sooner or later. 🙂